frogs and toads, the whole Eft order is unknown in those regions.

Our question "What is a Frog?" has now been somewhat further answered; but it cannot be completely so until the organisation of the animal has been more fully surveyed, and not only the relation of the frog to other Batrachians thus more clearly seen, but also the relations and affinities borne by the several orders of Batrachians and by the whole class to the other orders and other classes of the Vertebrate sub-kingdom.

Accordingly, we have now to make an acquaintance with more than those obvious and external characters which are found in the Frog, and to penetrate into its inner anatomy, surveying successively its bony framework and the various parts and organs which subserve the several actions necessary to its continued existence.

At the same time the more noteworthy resemblances presented by the Frog to other creatures will be pointed out. Thus we shall become acquainted with the relations existing first between the Frog and other members of its order; secondly, between the members of its order (Anoura) and its class fellows-e. other Batrachians; thirdly, we shall comprehend the degree of relationship existing between the Batrachia and the other classes of the Vertebrate sub-kingdom; and fourthly, we shall come to recognise certain singular resemblances which exist between the various groups of Batrachians (the Frog's order of course forming one), and some of the orders into which other vertebrate classes-especially the class of Reptiles have been divided.

The skeleton of the Frog, both external and internal, naturally comes first as the support and foundation of the other structures. The internal skeleton (or endo-skeleton) will include the bones of the head, i.e. the skull, backbone (already referred to), and the bones of the limbs. The external skeleton (exo-skeleton) will consist of the skin only. ST. GEORGE MIVART

(To be continued.)

ASTRONOMICAL ALMANACS* V.-The "Connaissance des Temps" under the continued direction of the old Academy

ET us return to the Connaissance des Temps of the old Academy.

LE

Jeaurat, who succeeded Lalande in 1775, adopted exactly the same principles as the latter; he, however, extended considerably the ephemerides of the moon, giving its declination for every six hours, to facilitate the calculation of the altitude, when at the same time only the distance could be observed. Méchain succeeded Jeaurat in 1788; he followed the example of his two predecessors, and like them, continued to take from the "Nautical Almanac " the distances of the moon, which Maskelyne had the kindness to send him even in manuscript.

the first part of our account of the Connaissance des Temps-a work at first completely independent, then published with the approbation of the Academy, which included at the time nearly all those who were occupied with astronomy; and afterwards entrusted to the care of the Bureau des Longitudes, a commission which still continues to be charged with its publication.

VI. The "Connaissance des Temps" under the Bureau des Longitudes

The first care of the Bureau was to entrust one of its members with the publication and direction of the Connaissance des Temps, thus showing, from the first, the true course which ought to have been adopted from the beginning, that a work of this kind demands strictly personal superintendence. Its choice fell upon Lalande, then Astronomer of the Observatory of l'Ecole Militaire. As to the calculations, however, the superintendence of this astronomer was more nominal than real; he was occupied mainly with the Additions which he had commenced in 1760, and towards which the bent of his mind," more of a collector than an inventor" carried him. Thanks to the great quantity of material which he had acquired, he made of these additions a work really useful, for at this time periodic scientific publications were very rare. His Journal d'Astronomie (history of astronomy during the preceding year), contains a mass of information of great value, even at the present day, to all who take an interest in the history of the science of astronomy.

As to the calculations, they were made partly by Bouvard, whom Laplace had appointed adjoint to the Bureau des Longitudes, and partly in the bureau of the Cadastre, under the direction of Prony, its chief. It was in the office of this celebrated engineer that the distances of the moon from the sun and from the principal stars were calculated, distances which ceased from that time to be taken from the Nautical Almanac. Let us, however, add, that up to the year 1806 the greater part of the other calculations of the Connaissance des Temps were drawn from the Nautical Almanac, with the view," according to the preamble, " of accelerating the publication." Despite this assistance, nevertheless, this work appeared only about a year and a half or two years in advance; it was then, at that time, completely useless to navigators who had to make a long round. The attention of the Bureau des Longitudes was not however turned in this direction. Its president was then the iliustrious Laplace, one of the glories of the mathematical sciences,

and who first knew how to deduce from the great discovery of Newton, all the consequences which it was calculated to yield.

Pierre Simon Laplace was born March 23, 1749, of a family of poor farmers of Beaumont-en-Auge (Normandy, Calvados). It is not known where he got the elements of his education, for when later he was raised to the highest honours, he had the weakness to wish to conceal his humble origin. Appointed in 1770, on the recommendation of d'Alembert, Professor of Mathematics at l'École militaire of Paris, he became in 1772 adjoint member of the Academy of Sciences, next succeeded Bezout as examiner of the pupils of the royal corps of artil

• Continued from vol. viii. p. 531.

Mécanique céleste, succeeded each other almost without this time, his beautiful memoirs on which he founded his interruption. Finally, in 1795, he was nominated presi held till his death, March 5, 1827. dent of the Bureau des Longitudes, a position which he

Under his leadership the Bureau was occupied mainly which are calculated in advance the positions of the difin perfecting and re-constructing the tables, by means of ferent stars. The tables of Delambre (the sun, Jupiter, Saturn, Uranus and the satellites of Jupiter, 1792), of Mayer (corrected by Mason, 1787), for the moon, of

Lalande for Venus and Mercury, showed with the observations very great errors which the theory of Laplace promised to eliminate, or at the very least to diminish. It was to the solution of these questions that Laplace directed the forces of the Bureau, and it was to their practical execution that he applied the resources which the budget granted him.

"To accelerate the work, the different parts were distributed to various members of the Bureau. The tables of the moon, on account of the constant use made of them in astronomy and navigation, were those which it was of special importance should be completed promptly; but the length of the researches, the magnitude of the calculations, which so complicated a theory required, only permitted the hope to be cherished that in the distant future errors might be made to disappear which had gone on increasing from day to day. This was the occasion of making an appeal to all astronomers, national and foreign, who might have sufficiently advanced works upon the lunar tables. With this object the Bureau des Longitudes was authorised to offer a prize."*

This prize of 8,000 francs was awarded by the Bureau to an astronomer of Vienna, Bürg, whose tables, based upon 2,500 observations, made at Greenwich from 1765 to 1795, were deemed the most accurate and convenient. At the same time, Delambre published new tables of the sun; Bouvard, pupil of Laplace, whom he had assisted in the publication of the Mécanique céleste (Laplace resigned to him entirely the detailed investigations and astronomical calculations), published Nouvelles Tables des planetes Jupiter et Saturne (1808), a new edition of which he brought out in 1824, to which were added tables of Herschel's planet, Uranus; Delambre published his Tables ecliptiques des satellites de Jupiter (according to the theory of Laplace and the totality of the observations made from 1662 to 1802); Burckhardt, a German astronomer, whom the conquests of Napoleon had given to France, published new Tables de la lune (1812), which, in the estimation of some astronomers, took the place of those of Bürg.

In

However, the impulse given by the splendid works of Laplace was not confined within the French frontiers. In Italy, a celebrated astronomer, Francisco Carline, published, in 1810, new tables of the sun, which were soon employed everywhere except in France.† Germany, a man of Science, who was at one and the same time an eminent lawyer, a distinguished captain, and an excellent astronomer, Bernhard von Lindenau, published, according to Laplace's theory, tables of Venus, Mars, and Mercury.

Unfortunately these excellent works, due to the powerful initiative of Laplace, were not made use of in the publication of the Connaissance des Temps.

In 1808, Delambre, one of the most eminent French astronomers, undertook the direction of the Connaissance des Temps. No essential change was made in the work till 1817; at that time the right ascension of the moon, which had until then been calculated only to a minute, was given to a second for noon and midnight. Sailors could thus determine the longitude of their ships with more exactness; and astronomers, instead of finding in the Connaissance des Temps only the indication of the time at which they ought to observe our satellite, could thus compare the results of their observations with those which the tables gave, and prepare the material for their improvement. Finally, in 1820, were introduced the diffe

Report of the Bureau des Longitudes, 1800.

"Esposizione di un nuovo methodo di construire le Tavole Astromische applicato alle Tavole del Sole" (Milan, 1810).

I "Tabule Veneris nova et correctæ ex theoria gravitatis, clarissimi de Laplace, et ex observationibus recentissimis in specula astronomica Seebergensi habitis erecta" (Gotha, 1810). "Tabula Martis novæ et correctæ ex theoria gravitatis, clarissimi de Laplace, et ex observationibus recentissimis erecta" (Essenberg, 1811). Investigatio nova orbita a mercurio circa soli descriptæ, accedunt Tabule Planetæ ex Elementis recens repertis et theoria gravitatis, illustrissimi de Laplace constructæ " (Gotha, 1813).

rences in right ascension and in declination of the sun, differences useful in calculating the preceding co-ordinates at an hour other than that of noon. This was still another advantage to sailors.

But these improvements were of very little consequence in comparison with those which astronomy, geography, and navigation demanded. Germany was the first to set an example in this direction, and the Royal Astronomical Society of London, after a long and learned discussion, came to the conclusion that they were necessary. Moreover, besides being incomplete, the Connaissance der Temps was full of errors from beginning to end, errata being found even among the errata themselves. Radical reforms were indispensable; but to make this clearly evident, we must return to the history of the “Nautical Almanac" and the Berlin "Jahrbuch."

(To be continued.)

MAN IN THE SETTLE CAVE

UNTIL the appearance of Mr. Tiddeman's paper in NATURE, vol. ix. p. 14, I had not fully realised the important issues which, according to him, depend upon the proper identification of the fragment of bone from the Victoria Cave to which he refers; nor was I aware that he was about to commit me in such very absolute terms to the opinion that it was human, but of this, as it turns out, I have no reason to complain.

Looking, however, at the apparent gravity of the statement, and knowing, also, that opinions might, and as I believe did, differ as to the origin of the bone, I have been induced to go into the matter again, and am now in a position to affirm that there is no room for the slightest doubt on the subject.

Mr. James Flower, the excellent and estimable articulator to the College of Surgeons, to whom I am under many obligations for assistance in such questions, and who at one time suggested, and had almost convinced me, that the bone was elephantine, has, after much search, found amongst the Museum stores of human osteology, a fibula which places the question beyond all doubt, and fully confirms the opinion I had come to. especially after seeing the Mentone skeleton, that the Victoria relic, pre- or post-glacial as it may be, is human. It is further important as showing that bones of the same conformation may occasionally be met with at the present day. GEO, BUSK

Harley Street, Nov. 14

NOTES

DR. A. DEW-SMITH and Francis M. Balfour of Trinity College, Cambridge, have been nominated by the Board of Senate (May 1, 1873), to study at the Zoological Station at Natural Science Studies, in accordance with the grace of the Naples under Dr. Dohrn, until the end of July 1874.

AT the General Monthly Meeting of the Royal Institution to be held on Monday first, a President will be elected in the room of the late Sir Henry Holland, Bart.

PROFESSOR TR QUAIR, of the Royal College of Science in Dublin, has been appointed to the Keepership of the Natural History Museum in the Edinburgh Museum of Science and Art. This gentleman was formerly one of the Demonstrators to the Professor of Biology in the University of Edinburgh, and is the author of several important contributions to Science.

MR. W. F. BARRETT, F.C.S., has been appointed Professor of Physics to the Royal College of Science, Dublin, in succession to the late Professor W. Barker. We feel sure that this appoint

ment will give great satisfaction. Sir Robert Kane, F.R.S., having resigned the post of Dean of Faculty to the College, for the purpose of spending his winters in the south of Europe, Professor Galloway has been selected to fill this post. It is said that there either are, or will very shortly be, a vacancy in the Professorship of Chemistry owing to Professor Sullivan's appointment to the Presidentship of the Queen's College, Cork. DR. E. II. BENNETT has been elected Professor of Surgery in the University of Dublin, in succession to the late Dr. R. W. Smith; and Dr. Thos. E. Little has been elected to fill the post of University Anatomist. In connection with news from the Dublin University, we may mention that it is understood that the authorities have determined to build a new museum for their anatomical and zoological collections. At present, in connection with the Medical School, there is a small collection of human

and comparative anatomy, and, in the Arts' School a very good collection of zoology. It is intended to combine these two in a new building. The College authorities would confer a great boon on natural science in Dublin if they would venture to go a step further and make their new museum contain all their biological collections. The advantages would be great of having the distribution of animals in space and time shown in connection the one with the other; and there is something incongruous in separating the specimens illustrating the past and present races of mankind from the zoological collection, and combining the specimens illustrating the anatomy and physiology of the human species with those illustrative of the other animals. For the convenience of the students, we trust that the extensive herbarium of the College may also be lodged under the roof of the new building, which, to be useful, need contain no lofty halls or grand corridors, but should consist of a series of welllit rooms, after the fashion of, we would suggest, that nicest of museums, the one for Economic Botany at Kew.

THE following memorandum on the Whitworth Scholarships, prepared by Sir Joseph Whitworth, has been ap proved by the Lords of the Committee of the Council on Education:-"I wish that candidates for my Scholarships in 1874, who, owing to the shortness of the notice, may not have been able to be in a mechanical shop for six months before the competition takes place, should be allowed to compete, but that if successful, their scholarship should not begin until they have worked six months in a mechanical shop. I think the same privilege should be accorded to candidates in 1875, who have not served eighteen months in a mechanical shop, the scholarship not beginning until this period is completed."

THE 120th session of the Society of Arts was opened on the 19th inst. with an address by the Chairman of the Council, Major-General F. Eardley-Wilmot, F.R.S.

THE magnum opus of three generations of botanists, De Candolle's Prodrom s Systematis naturalis vegetabilium," containing a diagnosis of every known species of flowering plant, has now been completed as far as Dicotyledons are concerned, and it is not intended to continue the work into the Monocoty ledons. In commemoration of the completion of the work, the Horticultural Society of Belgium has awarded M. de Candolle a special medal. The publication of the work was commenced in 1818.

THE trustees of the Gilchrist Educational Fund offer a scho

larship of the value of 50% per annum, tenable for three years at Girton College, Cambridge, to be competed for at the General Examination for Women, conducted by the University of London in May, 1874.

FROM the commencement of next year, The Gardeners' Chronicle and Agricultural Gazette will be divided into two papers,

each weekly, to be devoted to the interests of the two sister sciences.

DR. WILLIAM WALLACE, in opening recently the session of the Chemical Section of the Philosophical Society of Glasgow, spoke, among other things, of the endowment of research. From what he said on this subject, we think the following pointed remarks worthy of attention :-With regard to students who attended evening lectures and classes, a very great deal had been done for them by the Society of Arts, and by the examiners of the Science and Art Department, both of which had given great encouragement to the class of students whom they were intended to benefit. What was lacked most was a stimulus to men of the highest educational class. In this country, apart from professorships, there were no means of assisting that class except, perhaps, a few sinecures and the conferring of empty titles. In France, at least under the Imperial régime, when a man acquired renown in a particular line of investigation, a laboratory with all the best and most suitable appliances was immediately fitted up for him. Hence Paris was provided with a series of the most complete laboratories for metallurgy, for agriculture, for the sugar manufacture, and for many other branches of the science; and students might go to study a particular subject with the certainty that they would have a most efficient teacher and the advantages of a laboratory fitted up specially, and, as one might say, regardless of expense, with the apparatus and requirements necessary for the teaching and study of the subject. It appeared to him (Dr. Wallace) that the endowment of research would form a desirable stimulus for chemists, many of whom had the necessary education and talent, but could not afford the time nor the expense, often considerable, of obtaining the apparatus and materials required.

A SOCIETY of Physical and Natural Science was founded four years ago at Caracas, Venezuela; but the political agitations of the country have, until recently, hindered its development. Meanwhile it has commenced the publication of a Bulletin under the title of Vargasia, so named in honour of the American botanist Vargas. L'Institut learns, by a letter from Dr. Ernst, who is at once president, secretary, and treasurer of the society, that the present Government of Venezuela intends to promote, as much as it can, the growth of scientific studies, mainly by the establishment of various institutions for public instructior. Dr. Ernst, appointed Professor of Botany in the University of Caracas, where hitherto there has been no such chair, has been charged with the direction or rather the creation of a botanic garden and a museum of natural history. In the museum Prof. Ernst intends to collect-Ist, a herbarium of Venezuela; 2nd, a

general herbarium; 3rd, a collection relating to economic botany. He intends to publish in a few years a Flora of Caracas. Dr. Ernst appeals to European botanists and collectors for exchanges to assist him in the formation of these herbaria.

It is not often that Mr. Disraeli says anything which calls for particular notice in a journal of this kind, therefore it is with peculiar pleasure that we quote the opinion he uttered last week at the Glasgow banquet as to the share which Science has had during the present century in moulding the world. Coming from a man of his shrewdness and sentimentality withal, the words have a striking force. Speaking of the last fifty years, he said :-"How much has happened in these fifty years—a period more remarkable than any, I will venture to say, in the annals of mankind. I am not thinking of the rise and fall of empires, the change of dynasties, the establishment of Governments. I am thinking of those revolutions of science which have had much more effect than any political causes, which have changed the position and prospects of mankind more than all the conquests and all the codes and all the legislators that ever lived."

AT the first meeting of the Edinburgh Botanical Society for

the winter, Mr. James McNab, curator of the Royal Botanical Gardens, delivered an address on the change of climate in Scotland, which, during the last fifty years has undergone a considerable lessening of the summer heat. From this cause peaches and nectarines cannot be ripened to the same perfection in the open air as formerly, while asparagus, mushrooms, and tomatoes are gradually disappearing. The larch, in spite of the enormous quantities of seed annually imported, if declining in vigour, and there is a talk of substituting for is the Wellingtonia as a nurse-tree. Mr. McNab proposes that a central committee should be appointed to investigate the whole subject of the change of climate in Scotland.

THE following is an ephemeris (for oh Berlin time) of the comet discovered by M. Coggia at Marseilles, on the evening of the 10th inst: November 22, 14h 51m 25s-6° 8'2; November 30, 14h 14m 30s-22° 43'0; December 8, 14h 0m 17o -32° 1′.8. Its elements are:-T=Dec., 4'1348, Berlin mean time; 94° 23′ 14′′; 8 = 254° 14′ 9′′ ; i = 27° 2' 7". Mean Equinox, 18730 log. q. 9.83810.

=

ONE of the special results of the United States geological and geographical survey of the Territories, in charge of Prof. F. V. Hayden. during the past summer, has been the discovery that Colorado Territory is the centre of the greatest elevation of the Rocky Mountain chain. In Central Colorado the chain proper is about 120 miles broad, made up of three lofty parallel ranges, running mearly north-north-west, and flanked from the west by great plateaus and groups of peaks. Between the ranges lie the great elevated basins known as "parks." The front range, which rises abruptly from the plains, is seen from Denver in a grand panorama 120 miles long. From its snowy serrated crest rise many peaks between 13,000 and 14,000 ft. high. On the west side of the parks is the Park Range, whose highest group is at Mount Lincoln, this and Quandary Peak each rising to about 14,000 ft. The survey has established a permanent meteorological station at Fairplay, 10,000 ft. above the sea, and another at Cañon City, about 6,000 ft. These stations are all connected by a spirit-level line, and the comparison of their observations will be of remarkable interest. The National Range lies east of the Park Range, and is separated from it by the Arkansas Valley. West of the National Range rises the great group of Elk Mountains, five of whose peaks are 14,000 ft. high. So far as known, there are in the district explored during the past season by the survey 72 peaks, ranging from 14,000 to 14,200 ft. in height.

IN the article on Local Societies (vol. ix. p. 24) we inadvertently confounded the Manchester Natural History Society with the Microscopical and Natural History section of the Manchester Literary and Philosophical Society. The former of these is extinct-having handed its collections over to the Owens Collegeand also contributed a handsome sum of money to promote, permanently, the study of Natural History in the Literary and Philosophical Society. This endowment now enriches the Natural History section of that society. Manchester science will gain rather than lose by these changes. The defunct society was never more than the creator and guardian of a museum. That museum will still be preserved and increased, as well as utilised, by the College, whilst the Natural History section affords promise of a healthy career of scientific work.

M. CHARREL, of Marseilles, writes as follows to the Bulletin International, of the Observatory of Paris, on the invention of balloons :-In the literary history of the City of Lyons, published by Father Colonnia (1830, vol. i. p. 112), it is stated that in the reign of Louis le Debonnaire, the Archbishop of Lyons learned that some aërial navigators had fallen with their boat on the banks of the Saone, and were going to be put to death as sor.

cerers. He ordered them to be brought into his presence, and after having heard them, he caused them to be nonsuited (le fit mettre hors de procès). The memoir of the prelate bears such a character of authenticity as leaves no doubt of the fact. The following words are taken verbatim from the memoir: "Videmus exhibere vinctos quatuor homines; tres viros et unam feminam, quasi qui de ipsis navibus ceciderunt, quos. . . exhibuerunt în nostra presentia tanquam lapidandos." It follows, then, from this memoir, that already, in the ninth century, aerial navigation was known; how it was accomplished the memoir does not give any indication.

THE first Annual Exhibition of the West London Entomological Society, established 1868, will be held on December 2 and 3, at the "Mason's Arms," Tichborne Street, Edgware Road.

A Times telegram from Teheran, November 24, says that Colonel Baker and Lieutenant Gill have arrived at Teheran, and leave immediately for England, via Tabreez and Erivan. Travelling to the north from Meshed, they passed along the Turcoman frontier by Kelat, Abiverd, Dereguez, Annau, Astrabad, and Nissa. Striking south, they discovered the source of the Attrek at Karakazan, an extraordinary spring near Shirvan, and followed the course of the river ca considerable distance northwest of Bojnoord, until stopped by hostilities between Bojnoord and the Turcomans. Striking into the mountains, they were enabled to trace the course of the river until it fell into the plains, and also to observe the great range of mountains which runs along the whole Persian frontier from Sarakhs to Kizil Arvat. Existing conjectural maps of this country are quite incorrect.

the Art Exhibition and Museum of the Albert Institute ON the Ist inst. the Earl of Dalhousie formally opened of Dundee, which, with the previously opened portionsfree library and lecture-hall-form one handsome block of buildings. In the list of towns, with their scientific societies, published by us a week or two ago, we were surprised to see Dundee, so rapidly advancing in population and wealth, occupy so humble a place. We cannot see how towns like Leeds, Newcastle, Manchester, Glasgow, and others should have their flourishing and well-equipped scientific societies, while Dundee has only one small struggling society of young men, the Naturalists' Field Club. The neighbouring and comparatively stagnant town of Perth, with its large and efficient society, puts Dundee to the blush in this respect. We shall be disappointed if the opening of the Albert Institute in Dundee, a town so dependent for its commercial and manufacturing success on the applied results of Science, does not give an impetus to the study of Science. There are already Science and Art Classes in the town, and we hope to hear soon of the establishment of regular courses of scien tific lectures, such as those which are found in several of the large English manufacturing towns, and the formation of at least one flourishing scientific society and field club around the small nucleus already existing. We hope also that the collections in the museum will be made worthy of the wealthy town and be really representative of the treasures of the various king. doms of Nature. We feel sure that the citizens of Dundee only need their attention to be drawn to the backward state of their town in the matter referred to to rouse them to put it on a level in this respect with the large English towns.

THE additions to the Zoological Society's collection during the last week include an Eagle (Spizaëtus ?) from Burmah, presented by Mr. H. Fielder; a Macaque Monkey (Macacus cynomolgus) from India, presented by Mr. Gore; a pair of Jaguars (Felis onça) born in the Jardin des Plantes, Paris, received in exchange.

ON SOME RECENT RESULTS WITH THE TOWING NET ON THE SOUTH COAST OF

IRELAND *

1.-Mitraria

ONLY a single specimen was obtained of the little Mitraria, which formed the subject of the present communication, and neither its structure nor development was made out as completely as could have been wished. From the Mediterranean species described in a former communication (British Association Report for 1872), it differs in some points of structure and in the mode of annulation of the developing worm. It possesses the usual Mitraria form, that of a hemispherical dome having its base encircled by a band of long vibratile cilia. In the side of the dome a little above the ciliated band is the mouth which

leads into a rather wide pharynx clothed with a ciliated epithelium. The pharynx runs through the dome parallel to its base and opens into a capacious stomach which continues in the same direction until it joins the intestine. This then turns down abruptly at right angles to the previous portion of the alimentary canal, and then projects for a slight distance beyond the base of the dome, carrying with it hernia-like the walls of the base. The true body walls of the future worm, of which the Mitraria is the larva, seem as yet confined to the intestinal segment of the alimentary canal. They already present the commencement of annulation, which, however, exists only on the dorsal and ventral sides, while two broad bands of very distinct fibres may be seen, one on the right and the other on the left side, extending transversely from the dorsal to the ventral surface.

The ciliated band which runs round the base of the dome possesses a rather complex structure. It consists of two concentric rings an outer one composed of large oval distinctly nucleated cells, and an inner one of a granular structure and yellowish colour, in which no distinct cells could be demonstrated. The cilia form two concentric wreaths borne by the under side of the band, an outer wreath consisting of very long cilia, and borne by the inner edge of the outer portion of the band, and an inner wreath of much shorter cilia borne by the inner edge of the inner portion. The band with its cilia is interrupted for a very short space at the aboral side of the dome. There is probably at this spot an entrance into a watervascular system. No such system, however, was observed in the specimen, though the author had described in another species of Mitraria a system of sinuses which appear to exist in the walls of the dome, and which he regarded as representing watervascular system (Brit. Assoc. Report for 1872).

Occupying the very summit of the dome is a large, somewhat quadrilateral ganglion, from which two distinct filaments are sent down, one on each side of the alimentary canal, but he was not able to follow these filaments to their destination. The bilateral symmetry of the ganglion suggests its formation out of two lateral halves. Though its very superficial position gives it the appearance of being a mere thickening of the walls, the view here taken of its being a nervous ganglion seems to be the only one consistent with its relations to the surrounding parts.

On each side of the pharynx, a little behind the mouth, is a small oval ganglion-like body from which a filament runs to the ciliated band. Some delicate filaments may also be seen lying between the pharynx and the walls of the dome on which they seem to be distributed, but the author could not trace them to any distinct ganglionic centre.

The great apical ganglion carries two very obvious black ocelliform spots, and besides these two clear vesicles enclosing each a clear spherical corpuscle. The two vesicles may probably be regarded as auditory capsules.

The further development of this larval form has not been observed. It probably consists chiefly in the continued prolongation of the alimentary canal beyond the base of the hemispherical dome, the completion of the annulation by its extension to the right and left sides, and the gradual contraction of the dome and final absorption of the ciliated band.

pointed out by Alex. Agassiz in his valuable and elaborate memoir on Tornaria and Balanoglossus. The species appears to be different from those hitherto described. The gills had not begun to show themselves, and there were but traces of the 'lappets" described in other species as appended to the posterior extremity of the stomach.

The author believed that he could distinguish a minute ganglion on each side of the oesophagus ; filaments were sent off from it to the neighbouring parts, and the two were connected to one another by a sub-cesophagal commisure. The water-vascular chamber was very distinct, but the so-called heart was not observed; while within the body-cavity, lying close to the dorsa pore and over the canal by which the great water-sac communicates with the external medium, was a small, closed, rather thick-walled vesicle containing numerous oval corpuscles. Of the nature of this vesicle the author could not offer any opinion. The cushion-like body which occupies the summit of the larva exactly as in Mitraria, and supports the two ocelliform spots, extends from this to the walls of the water-sac. The author, was very distinct, and so also was the contractile chord which however, could not here, any more than in Mitraria, regard the cushion-like body as a mere thickening of the walls; he believed it to be a nerve-mass, and thought he could trace two fine filaright and the other towards the left side of the alimentary canal, ments proceeding from it and running down, one towards the but he was not able to follow them for any distance, and he does ficial situation of this body, which makes it resemble a mere not regard their existence as confirmed. The extremely superthickness of the walls, is paralleled by that of the great ventral nerve-mass in Sagitta.

The contractile chord which runs to the water-sac is probably attached to a capsular covering of the ganglion, rather than directly to the ganglion itself. This chord, though showing strong contractions by which the summit of the larva is drawn down towards the water-sac, is of a homogeneous structure, presenting no appearance of distinct fibrilla or of other contractile

elements.

The author instituted a comparison between Tornaria and Mitraria. We have in both the external transparent pyramidal anal orifice, enclosing an alimentary canal which is divisible into or dome-shaped body, with a lateral oral orifice, and a basal direction in its course from one orifice to the other;* we have in three regions, and takes a partly horizontal and partly vertical both, near the base of the body, the circular band which carries long vibratile cilia accompanied by a row of pigment spots, and in both the cushion-like ganglion carrying ocelli.

From Mitraria, Tornaria chiefly differs in the presence of the thick sinuous and convoluted bands which give it so close a resemblance to certain Echinoderm larvæ, and which are entirely absent from Mitraria, and in its water-vascular system with the contractile cord which extends from this to the apical ganglion. If a water-vascular system is present in Mitraria, it consists there of a system of sinuses excavated in the walls of the dome, but without any representative of the great central sac. In Mitraria the great apical ganglion carries not only the two ocelli, but also two capsules, probably auditory; these capsules do not exist in Tornaria. Ir Mitraria the two nerve chords alimentary canal are very distinct; in Tornaria, if they exist at all, which the apical ganglion sends down one on each side of the they are by no means obvious. Finally, the ciliary circlet is simple in Tornaria, while in Mitraria it is double.

According to Alexander Agassiz's account of the development of Tornaria into Balanoglossus, the great transverse circlet of cilia becomes, by the elongation of the body, gradually pushed backwards, so as to form the anal ciliated ring of the young worm; in Mitraria the great ciliary circlet remains unchanged during its development acquiring a new anal wreath of cilia. in position, and is probably ultimately absorbed, the worm

3. Ametrangia hemispherica (nov. gen. et spec.) Among the most abundant products of the towing-net was a little hydroid medusa, remarkable for the want of symmetry in the distribution of its gastro-vascular canals. It is of a hemiand provided with very numerous (more than 100) marginal tenspherical form, with the base about half-an-inch in diameter,

tacles, which are very extensile, and may at one time be seen floating away to a length of three or four inches and at another coiled into a close spiral against the margin of the umbrella. • In the species of Mitraria described by J. Müller and by Metschnikoff, both oral and anal orifices are basal, and the alimentary canal presents a ushaped curvature