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the Hentys sail nearly half-way round the globe to architecture, and similarly second-hand. The fact is harpoon the whale, or did the whale travel into the that our persistent cramming of Latin is a monkish other hemisphere to avoid further communications inheritance ; the reasons alleged for its continuance with the Hentys?

are mere afterthought apologies that were never What is the range of migration of whales? Do imagined by its founders, who were clerics, and ignothey cross the equator? I have seen several in rant of everything but the language of the church. latitudes of considerable variation ; those in lower One of the most puzzling manifestations of latitudes going straight ahead as bona fide travellers, “instinct" is that presented by the overland and at a speed that would soon cover a few thousand migration of fishes. That they should leave ponds miles.

which are gradually drying up is easily understood, as If scientific mariners and ocean passengers would the water necessarily becomes more saline or harder record the sighting of whales, with date, latitude, as the evaporation proceeds, but that they should steer longitude, and direction of the monster's course and directly towards larger ponds, or towards rivers, as we probable speed, I think we might obtain some are told they do, is very astonishing. My own susinteresting information. I have little doubt that on picion is that they do not ; that they simply wriggle the largely frequented ocean tracks, certain whales blindly through the wet grass and either perish or might thus be identified, as seen in different parts of survive as it happens; that the wonderful sense of their journey from different ships. As there is always direction exists only in the imagiration of those who a lower ice-cold current in all the North and South describe the migration. In a country that slopes ocean highways, the cetacean tourist may at any time towards a river it is of course probable that the take a refreshing dive when the surface is oppressively | majority will proceed in the direction of least warm.

resistance i.e. downwards, and thus eventually reach Among the papers published in the “ Bulletin of the river. the Philosophical Society of Washington, for 1884,"is! I have observed that pond fishes, such as eels, tench, one by Mr. Washington Matthews on “ Natural Natu and carp, have remarkable powers of remaining alive ralists." The author finds that the aboriginal Indians out of water; eels for several days ; carp and tench are students of Natural History, quite outside of the remain alive in damp grass above twenty-four hours; animals and plants they require for use. He says: in cool weather double this time. “Nature,” June “I never failed to get from an Indian a good and 4th, page 111, says : “The eels of the ponds in the satisfactory name for any species of mammal, bird, or woods of Vincennes leave them every spring in large reptile inhabiting his country; and I have found their numbers, making their way to the Seine or the knowledge of plants equally comprehensive. The Marne, several kilometres distant. They take Indians are, in this respect, as a class, incomparably advantage of rainy weather, when the herbage is superior to the average white man." The editor of wet, and their instinct guides them directly to their “ The Journal of Science” quotes the above, and destination." adds: “ This evidence shows how much our powers of Careful observation of the proceedings of these observation have been stunted by the exclusive, or, at eels would be very interesting. Do they ever travel least mainly, literary character of our educational up a slope, or transversely to it? If they only systems. From childhood our attention is fixed, descend from higher ground downward to the river, upon words, written or spoken, and except, among there is no more occasion to invoke any mystery of specialists, inobservance has followed.”

instinct to explain such a course than to attribute the It appears that my own remarks in the May seaward flows of the river itself to the directive number of SCIENCE-GOSSIP, on the still surviving instinct of the water. exaltation of the Latin classics in modern education, The origin of the iron pyrites which exists in all have brought forth a remonstrance from Dr. P. Q. our coal, and in some seams so abundantly as to Keegan (see page 138 of June number). He render them nearly worthless (the “brassy" coal misunderstands me. I by no means advocate the of Flintshire for example) has long remained an exclusion of literature, but the contrary; and would unsolved enigma. M. Dieulefait, in a communication give precedence far above all to English literature, to the Academy of Sciences, has shown that the ash which is practically excluded from the present of plants constituting the nearest surviving represencurriculum of grammar schools, and miserably tatives of those of the carboniferous epoch, contain neglected in our universities. If there really is any much more sulphur than ordinary recent plants. This basis for the popular scholastic notion that ancient is especially the case with the Equisetaceæ. I should literature is especially elevating, why not be con add that besides the gold-like crystals of iron pyrites sistent, and commence with Greek? There is origin- there are varying proportions of sulphate of calcium ality, subtlety, ideality and philosophy in the Greek in coal. If this large proportion of sulphur was classics, those of the Romans are at best but clumsy common to all the plants from which the coal was imitations; their poetry and philosophy standing as formed, M. Dieulefait's solution of the problem is much below those of the Greeks as their sculpture and satisfactory.

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Mr. Galloway has done good service in his perse- , returning to the soil nearly all we take from it, vering study of the agency of coal dust in producing thereby restoring our rivers to their pristine purity colliery explosions.

and vastly increasing our food supplies. If the still He has completely refuted the old-established continuous downfall of rentals urges the landlords to notion that they are simply due to the combustion of give to this subject the degree of practical attention the hydro-carbon gases to which the miner gives the | which their own interests demand, we may have name of “fire-damp," Mr. Galloway has demon- | reason to exclaim with the banished duke, that“sweet strated clearly that fine coal dust stirred into ordinary are the uses of adversity.” air forms a mixture having fearful explosive energy. The only question which he leaves debateable, is whether a destructive colliery explosion may be due to this alone, or whether an initial explosion of fire

TEETH OF FLIES. damp always occurs. That such initial explosion, by stirring up the coal

By W. H. HARRIS. dust otherwise lying dormant, and at the same time

No. VI. igniting it, may be in many cases operative is not to

(STOMOXYS CALCITRANS.) be doubted; but the very practical and very serious question, of whether a pit free from outbursts of

THE genus from which the present illustration is carburetted hydrogen may nevertheless be liable to 1 taken, forms a small one of the order Diptera, explosions if dry and carelessly worked, still remained embracing, according to Walker, three species only, open. Mr. Galloway contends that the dust alone viz., Stomoxys calcitrans, S. irritans, and S. stimulans. is dangerous ; others have denied this, notably so

Towards the close of summer, and during the autumn, MM. Mallard and Le Chatelier in their report to the French Commission du Grisou. Since this a

ir Prussian Fire Damp Commission has been appointed, and has investigated the subject very thoroughly, their results confirming those of Mr. Galloway.

The subject is of great and growing importance. We are rapidly exhausting our old coal seams, and continually going deeper and deeper to supply the voracious demands of our blast furnaces, gas works,

ph e wasteful fire-places, &c., and as we get deeper, we come upon dry workings, where, unless special

Fig. 98.-Mouth of Stomoxys calcitrans X 14 diam. ph, ph,

pharynx ; lbr, labrum ; 1, lingua ; la, labium; mp, maxillary precautions are taken, every shot stirs up a cloud palpi; le, levers or fulcra of labrum. that may contain particles fine enough to produce a local explosion, the which stirs up another cloud to | S. calcitrans enters our houses, and, by its persistent explode in like manner, and so on to fearful results, and aggravating attacks on mankind, does much to even in a pit where naked candles may be carried destroy the equilibrium of the best of tempers. It is with safety if the air is not violently agitated. The commonly known as the stable fly, but is not at all practical bearing of this upon the kind of pre disinclined to pay attention to oxen, &c. So similar caution demanded is self-evident. The source of is it in general outward appearance to the ordinary danger being so different from that of fire damp, house-fly, that, unless special attention is directed to the precautions must be modified accordingly. the mouth organs, it may easily be mistaken for

The commercial results of sewage farming are Musca domestica, but while the latter is comparausually very discouraging. This however has not tively an inoffensive creature, the former is an been the case at Forfar, where, according to the unmitigated nuisance ; in fact, the only redeeming published accounts, a field of 38 acres, which cost point about it is of a purely negative character. £3,600, or £94 per acre purchase money, has yielded

Possibly by stimulating the attacked party to take a profit, the total cost of working being £220 155. some exercise to rid the pest, it may do some good, including horse labour, manual labour, seed and but the benefit thus derived is more than counterrepairs, and auctioneer's commission. The receipts balanced, if a quiet after-dinner nap has been were £509 125. 6d. leaving a balance of £288 175. 6d. 1 contemplated. The proboscis is cylindrical, with an or 8 per cent. on the capital outlay. This however does enlargement near its point of attachment to the head. not include any management expenses, but supposing Unlike the Muscidæ, it is incapable of being witha capitalist to have undertaken it, and managed his drawn, but always projects from the head downward own business and thereby saved the £24 55. 2d. charged and slightly forward. It is chitinous, black, hard, and for auctioneer's commission, he would have obtained a beautifully polished. Under the microscope, about return of nearly 9 per cent. with very little trouble. three-fourths of the circumference is seen to be We appear to be within measurable distance of thickly set with very delicate transverse striæ, and a fourth part at first-sight apparently quite devoid of any marking. By careful manipulation with a couple of needles this may be withdrawn, and will be found to consist of two distinct parts, an outer one, or sheath, through which the enclosed needle-like organ freely moves. When the proboscis is in its natural condition, these parts are seen to enter, and are capable of being moved within the cylinder, which extends for a short distance towards the end of the proboscis. A reference to figure 99 will give

and necessary to some extent if we desire to comprehend the action of the mouth.

The free ends of these organs are very thin and delicate, and quite inadequate as a means of inflicting a puncture. Their use undoubtedly is to convey the liquid aliment to the cesophagus by constantly sliding the parts within each other, on the same principle as that employed in some instances for lubricating machinery by means of the needle lubricator, which may be familiar to many.

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some idea of the two parts referred to, the main | The enlarged portion of the proboscis is liberally portion of the proboscis being omitted.

provided with muscles, and from these tendons a is the sheath (Labrum) carrying the needle, b extend down to the mouth; they are very numerous, (Lingua) in its concavity, while the convex side sufficiently so to supply individual movement to the being outward completes the cylindrical outline of teeth and other organs therein contained. the proboscis. The aperture at the extremity of the In order to display these organs a different mode sheath agrees in size, and comes into close proximity of procedure is necessary to that employed in to the mouth, or rather that part of it in which the Muscidæ. The end of the proboscis must be cut off, organs of dentition are situated, and to which these and the point of a very fine knife inserted in the notes are chiefly intended to refer ; but the whole organ opening and laid open, similar to what is done to is so full of interest I have been led to make these display the gizzard of a beetle. The operation is remarks as bearing in some measure upon the subject, well calculated to test the patience of the operator, and many failures will occur before a satisfactory view will be obtained, unless singularly fortunate or

CHAPTERS ON FOSSIL SHARKS AND

RAYS. proficient. The teeth are of two distinct types, and associated

By ARTHUR SMITH WOODWARD. with them are other organs to which reference will be made. The primary set are stout and admirably formed for puncturing the skin of the victim selected.

SPINACIDA. They are five in number (dealing as heretofore with

| THE Spiny Dog-fishes and their allies form a large one half of the mouth), each of these carries one 1 family whose paläontological history appears rather small point or denticle, and, in addition, they

to begin with the deposition of the Lias. So far as is are very finely serrated, three on one side only, the

known, Palæospinax, from the Lower Lias of Lyme two central ones on both sides, but it requires a high

Regis, is the fore-runner of the race, and the earliest power to see this distinctly. In this respect the

example of a living genus is Spinax primavus, from figure is slightly exaggerated for clearness' sake.

the Cretaceous rocks of Mount Lebanon. Immediately behind these teeth, and situated near to

Exceedingly perfect specimens of Palaospinax their apex, is a set of short curved appendages, a have been discovered in the well-known Liassic fishpair being allotted to each tooth. They are quite

beds of Lyme Regis, and by a study of these remains opaque and uniform in thickness throughout. Their

Sir Philip Egerton has been able to elucidate the use appears to be for maintaining hold while the

structure of the genus ;* space, however, prevents us other instruments do the cutting and wounding.

from entering far into the anatomical details, and it Next follow a set of sabre or lancet-shaped teeth,

is only possible to glance at one or two of the most very fine at the points, and by the lightness of colour,

prominent features. The ordinary length of the delicate in structure, but, nevertheless formidable in

shark being not much more than eighteen inches, the number for the size of the mouth. These are the

teeth are very minute, and the use of a lens is organs for making an incision. When this has been

necessary to reveal their characteristics. They are accomplished, the small hooks are inserted, and the

remarkably Hybodont in shape, but a great difference primary set soon completes the work. The margin of

exists between those of the upper and lower jaws, the mouth is very thickly set with strong hairs, each

and there is also considerable variation even in the springing from a well-defined base, apparently capable

dentition of the same jaw ; fig. ioi represents a tooth of movement. The integument is quite opaque, but

from the anterior part of the upper jaw, and fig. 102 near the margin assumes a tesselated appearance,

a lower tooth of corresponding position. The dorsal the original cellular structure being preserved, the

fin-spines (fig. 105, A, B) are likewise of small size, and cells are partly filled with pigment, thus leaving the

their external surface is smooth, exhibiting no margins well defined.

ornament except a few scattered tubercles and It will be observed there are no pseudo-trachea

indistinct lines of growth at the base of the exposed present as in the Muscidæ, and as these play an

portion : it is interesting to notice that the anterior important part in the collection and conveyance

spine (A) is smaller, stouter, and more recurved than of the food, their absence is fully provided for in the

the posterior (B)—the reverse of what occurs in organ I have attempted to describe.

Hybodus and Acrodus. The slender body is covered If these creatures are plagues when alive, to the

with fine shagreen, and the fins appear to have microscopist, they are in death doubly so, at least

possessed strong supporting rays of cartilage ; and, with regard to their mouth organs. Small, hard, and

although the second dorsal fin almost corresponds in very brittle it is extremely difficult to obtain a

position with that of Cestracion, there are indications fairly representative mount, but patience and per

of the anal being merged with the caudal (according severance will accomplish much. In this case it has

to Egerton), and this is a special character of the done a little to explain the wonderful contrivance

family now under consideration. employed to replenish the larder of this little

The history of Drepanephorus affords a typical creature.

example of the slow but steady progress of palæontological knowledge. In 1822, some spines and

vertebræ from the Chalk of Lewes were referred by SLUGS BITING.-It is stated by Rimmer that Dr. Mantell to the Teleostean “File-fish,” Balistes. Testacella will “ bite savagely.” I have never In 1838, Prof. Agassiz showed that the fossils in succeeded in making it do so, but the other day on question really belonged to a shark, and considered handling a large black specimen of Arion ater the them to indicate an extinct species of the living animal at once seized one of the folds between the genus, Spinax, which he designated S. major. fingers of the hand on which it was placed. The Twelve years later, Sir Philip Egerton described rasping action could be distinctly felt, and after he had been allowed to operate for about a minute the

* Mem. Geol. Surv., Dec. XIII., 1872, Pl. VII. ; see also

" Quart. Journ. Geol. Soc.," vol. xxix., 1873, p. 420; and skin was seen to be abraded.-W. Gain, Tuxford. | "Ann. and Mag. Nat. Hist.," [5], vol. vii., 1881, pp. 429-432. of a new Shark, named Chlamydoselachus from the Japanese seas, of which the dentition is exceedingly similar; in fact, Professor Cope has ventured to refer the latter to the Palæozoic

some scattered teeth from the Chalk, under the name and the most recent contribution* to the subject, by of Cestracion canaliculatus, because they seemed to Mr. J. W. Davis, of Halifax, seems to show that the differ but little from those of the recent Cestracion, | latter is most probably the case. except in their smaller size and the possession of a The ordinary fossil remains of this family met minute channel passing obliquely through the root of with in Britain, are confined to Carboniferous strata, each. Three years after this, in 1853, the same and present themselves in the form of detached spines ichthyologist announced the discovery of a specimen (called Pleuracanthus and Orthacanthus) and teeth proving the teeth and spines to belong to one fish; | (known as Diplodus), but the Continental specimens, and in 1872 Sir Philip, also, published detailed to which we shall shortly refer, are much more descriptions of all the more important specimens complete and occur chiefly in the Lower Permian. then available, and proposed the generic name by The spines are long, usually straight, and tapering which this Selachian is now known.* Fig. 106, A, B, to a point, with a smooth or finely striated surface, are drawings (half nat. size) of the first and upon some part of which are arranged two longitudinal second dorsal fin-spines, which are only marked by rows of denticles; they much resemble the spines of lines of growth and do not appear to have been very | recent Rays in external shape, but differ from those deeply implanted in the soft parts ; and figs. 103, 104 of such as Trygon and Myliobatis in not being solid, represent an anterior and posterior tooth, the former | but possessing a hollow cavity which opens at the base. quite prehensile, and the latter adapted for crushing, Fig. 107 represents a typical example of the Pleuracanas is the case in the front and back teeth of thus spine, half the natural size, and the diagrammatic Cesiracion. D. canaliculatus is the only species transverse sections, figs. 108, 109, show the difference of the genus at present recognised, and its remains between this and the form originally termed Orthaoccur chiefly in the Chalk, although other English canthus; the latter, it will be observed, is much Cretaceous deposits have yielded a few fragments. more cylindrical than the former, and the rows of

denticles are placed close together along the back, RHINIDÆ.

instead of far apart along the sides, but in the paper

already mentioned, numerous intermediate forms are Our object in this series of articles being to described, which demonstrate that these are only the dwell chiefly upon those Selachian fossils that two extremes of a nearly continuous series. most commonly come under the notice of English

The little bodies known as Diplodus (fig. 110) consist collectors, and to summarise the results of the latest

of a thick bony base, upon which are fixed two researches relating to such, a passing notice will

comparatively large diverging denticles, with a suffice for the small, but interesting family of

smaller denticle and a little flat-topped or rounded “ Angel-fishes” and “Monk-fishes.” None of their

boss rising between. They occur not unfrequently remains are known to occur in British strata, and the

at many Coal Measure localities, and considerable Lithographic Stone (U. Oolite) of Bavaria and

numbers are sometimes met with in association. France appears to be the only Continental deposit | Agassiz originally described them as teeth, and this yielding examples of importance. These have been

seems to be the view now generally accepted, but referred to the living Rhina (= Squatina) and the

some palæontologists have expressed the opinion doubtfully distinct genus Thaumas : though the gill

that they are simply dermal tubercles analogous to the openings are lateral, the general form of the body is

prickles of the “ Thornback" and other recent Rays.t much like that of the Rays, and there are no dorsal

The Permian specimens of Pleuracanthus (Xenaspines.

canthus) found in Germany elucidate many important

details in the anatomy of the interesting Selachians PLEURACANTHIDA (XENACANTHIDA). whose fragmentary remains have just been noticed.

Some examples, in fact, exhibit nearly all the hard This is an extinct family, of which much yet

hyet parts of the fish in their proper relative positions. remains to be learned. It comprises the various

The body is slightly flattened, and the general shape forms that have been described at different times

recalls that of Rhina ; there are numerous teeth, of under the generic names of Pleuracanthus, Diplodus,

the Diplodus type, f in the jaws, and the large Orthacanthus, Xenacanthus, and Triodus, and which it is now almost universally agreed to unite under the first (the earliest) of these terms. Triodus is un * Quart. Journ. Geol. Soc. London, vol. xxxvi. (1880),

pp. 331-336. References to previous literature are here given. doubtedly identical with the previously-described + " Ann. and Mag. Nat. Hist." (4) vol. i., 1868, p. 371. Xenacanthus, and there is no doubt, likewise, that

* We may here note that this type of tooth is not exclusively

confined to Pleuracanthus, having been found in association this is the same as Pleuracanthus. The chief dis. with at least one other spine in the Lower Carboniferous, (T.

Stock, "Nature," vol. xxvii. 1882, p. 22). Further, recent puted point is, whether Pleuracanthus and Ortha

numbers of the American Scientific Journals contain notices canthus really differ generically, or merely specifically,

genus, but the figures show the fish to be very different in form * Mem. Geol. Surv., Dec. XIII.

and indicate the absence of a spine.

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