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the luckless host. This would be beneficial to the future parasite, as securing a better hold; and variations in this direction would consequently be preserved as advantageous. As soon as the ducts had penetrated, an osmotic interchange of fluids would take place, the balance of benefit being against the “ host; ” and since this source of nourishment would be more constant than the somewhat precarious livelihood casually gotten by the waving cirri, the latter organs, together with their neighbours, the trophi, finding their “ occupation gone,” would in time atrophy, while the quondam cement-ducts would become nutriferous rhizomes. Those Cirripedes having a. constant means of subsistence would be better off than their less fortunate relations who still kept on “living from hand to mouth,” and would outstrip them in the “struggle for existence.” Protected by the abdomen of its Porcellanus host, or by the lodging “ annexed ” by the hermit Pagur'us, it would gradually leave off its calcareous coat and become at last “only a soft sack filled with eggs, without limbs, without mouth or alimentary canal, and nourished, like a plant, by means of roots, which it pushed into the body of its host. The Cirripede had become a Rhizocephalon.” * The Anelasma squalicola, which lives upon sharks in northern seas, represents the halfway stage of this transformation. Here the shell-less test is supported on a peduncle which is beset with hollow filaments which “penetrate the shark’s flesh like roots.” On the other hand, the cement-glands are absent, the parts about the mouth minute, and the cirri destitute of bristles.
Having begun the article, now concluded, with myths, we bring it to a close wit “ matters of fact; ” but we think that it will be conceded, that sometimes “hard facts ” and even scientific speculations, are no less strange than fiction and the wildest flights of fancy.
LIST OF PRINCIPAL WORKS REFERRED TO.
Burmeister, Hermann. “Beitriige zur Naturgeschichte der Rankenfiissler” (Cirripedia). 4to. Berlin, 1834.
Cams, Victor. “Icones Zootomicae.” Tab. x. figs. 33—44. Leipzig, 1857.
Clark. “ A List of Dissections in the University Museum, Cambridge.”
' It is significant that the Oz'rripedia and Rhizocephala, when in the Nauplius stage, have more points in common than they have with the Nauplii of other Crustaceans.
Coldstream. Article “ Cirrhopoda,” in vol. i. of Todd’s “ Cyclopaedia of Anatomy and Physiology.”
Darwin. “A Monograph on the Sub-class Cirripedia.” 2 vols. Ray Society: London, 1851-54.—“ A Monograph on the Fossil Lepadidm,” and “A Monograph on the Fossil Balanidaa.” Palmontographical Society, 1851-54.—“ On the Origin of Species,” p. 211, 3rd edit. London, 1851.
Gegenbaur. “Grundziige der Vergleichenden Anatomie.” 2te Aufl. Leipzig, 1870.
Gerarde. “Herball, enlarged and amended by Thomas Johnson, Citizen and Apothecarye of London.” p. 1589. London. 1633.
Gerstaecker in Bronn’s “Klassen und Ordnungen des Thierreichs.” 5ter Bd. “ Arthropods.” (Rankenfiissler), pp. 406—589. Taf. i.—vi.
Gesner. “ Conradi Gesneri, Tigurini, medicinae et philosophies professoris in Schola Tigurina Historia Animalium.” Liber iii. p. 109. Francofurti.
Giraldus Cambrensis. “Topographia Hibernica.” Cap. xv. “De bernacis ex abiete nascentibus, earumque natura.”
Goethe. “Die Lepaden.” 1823. “ Slimmtliche Werke.” 27ter Bd. s. 280. Stuttgart, 1858.
Haeckel. “Natiirliche Schepfungsgeschichte.” 2te Aufl. s. 487. Taf. viii—ix. Berlin, 1870.
Hoeven, Van der. “Handbook of Zoology,” translated by Clark. Vol. i. pp. 598—621, p. 633—640, pl. xii. fig. 5. London, 1856.—“Philosophia Zoologica,” pp. 235—347. Lugdun. Batav. 1864.
Huxley. “An Introduction to the Classification of Animals,” p. 125. London, 1869.
Martin, Saint-Ange. “ Mémoire sur l’Organisation des Cirripédes.” “ Mémoires présentés a l’Acad. des Sciences de Paris.” Tome vi. p. 513. 1835.
Maundevile. “The Voiage and Travaile of Sir John Maundevile, Knt.” Reprint from the Edit. of 1725, edited byT. O. Halliwell, p. 264, cap. xxvi. London, 1866.
Moray. “A Relation concerning Barnacles, by Sir Robert Moray, lately one of his Majesties Council for the kingdom of Scotland.” Phil. Trans. No. 137. 1677—78.
Miiller, Fritz. “Facts and Arguments for Darwin.” Translated by Dallas. London, 1869.
Miiller, Max. “Lectures on the Science of Language.” 2nd Series. Lect. xii. “Modern Mythology.” London, 1864.
Robinson. “ Some Observations on the French ‘ Macreuse ’ and the Scotch ‘ Bernacle.”’ Phil. Trans. vol. xv. 1685.
Rolleston. “Forms of Animal Life,” p. cxviii. Oxford, 1870.
Spencer, Herbert. “The Principles of Biology.”
Thompson. “Discovery of the Metamorphosis in the second type of the ‘ Cirripeda,’ viz. the Lepades, completing the Natural History of these singular Animals, and confirming their aflinity with the Crustacea.” Phil. Trans. 1835, p. 355, and pl. vi.
Troschel. “ Handbuch der Zoologie.” 7b Aufl. Berlin, 1871.
EXPLANATION OF PLATE CIV. ‘
From a drawing taken " from the woodcut in Chapter xxvi. of Sir John Maundevile’s “ Voiage.” This should be compared with the woodcut'l' at p. 388, borrowed by Prof. Max Miiller from Gerarde’s “ Herball.”
Taken from fig. 3 of a plate in the “Phil. Trans,” accompanying Sir Robert Moray’s “Relation concerning Barnacles.’ This seems to supply a link between the mythical epoch, as represented by Gerarde’s figure, and that of fact, as represented by the following diagram.
Diagram of the capitulum of a Lepas, showing the relations of the various factors of the shell, reduced and modified—cg. by turning it upside down, for better comparison with fig. 2 —from Darwin’s figure (fig. 1) at p. 3 of his Monograph on the Lepadidw. (c) Carinai (t) Tergum. (s c t) Scutum. (u 1) Upper Latus. (s c r) Subcarina. (c l) Carinal Latus. (i m l) Infra-median Latus. (r l) Rostral Latus. (s r) Subrostrunr. (r) Rostrum.
Drawn by the author from a specimen belonging to the University Museum, Oxford. The bottle containing it is thus labelled :—“ Conchoderma Hzmterz', on carapace of a crab from Amoy. The eye is situated in this species on the oral side of the adductor, the reverse of its position in quas.” On the right side, three of the Cirripedes are in situ, while, on the left, only one out of two originally adherent remains, the position of its former neighbour being indicated by a scar-like pit in the carapace of the crab.
Modified from woodcuts in Darwin's “ Monograph of the Cirripedia,” illustrating the homologies between this group as represented by a Lepas (fig. 6), and the Crustacea, as represented by one of the Stomapoda (fig. 5). Those “ somites ” of the Crustacean body, which are present in the Cirripede, are coloured dark, those being merely left in outline which have no representative in the latter group. (p) Peduncle. (c) Capitulum. (c r) Cirri. (e) Eye. ((1) Antennae. (0p) Carapace.
Reduced and modified from figures in Tafs. viii. ix. of Prof. Hackel’s “Natiirliche Schopfungsgeschichte.” Fig. 7 is the larval form (Nauplius) of a Lepas, such as may be conveniently represented by the preceding figure, while figs. 8, 9 respectively illustrate the Nauplius and adult stage of a
‘ By kind permission of Messrs. Ellis and White, the publishers.
Crustacean proper (Cycbps). The main object of these figures is to demonstrate the fact that, however dissimilar in their adult forms may be the representatives of the various divisions of the Crustacean stock (“ Stammform ”), they have a striking similarity, making allowance for difl'erences in minor particulars, in their larval stage.
FIG. 10. “ Complementary male ” of Scalpellum Vulgare attached over fold
in “ occludent margin” of the seutum of the hermaphrodite. Reduced and modified from fig. 37, tab. x. of Carus’ “ Icones Zootomicse,” taken from fig. 9, pl. v. of Darwin’s monograph. (0) Orifice of sack of male. (p) Spinous projections above the rudimentary valves. (0) A transparent border of chitine—supporting long spines—which forms a border to the “occludent margin” of the scutum of the hermaphrodite. (d) Depression for the adductor scutorum muscle of the hermaphrodite.
At the top of the figure are represented, as seen through the
whole thickness of the animal, the prehensile larval antenna.
For comparison with the above, see the figure of the male of
Scalpellum regium, given in one of Prof. Wyville Thomson’s “Notes from the Challenger,” in “Nature,” August 28. 1873.
AMERICAN RECORD OF SCHINCE.‘k
HE Americans are attempting in their own country what has been attempted with the most signal failure in this. They are trying
to publish, with successful results, an annual work recording the progress made, not only at home, but throughout the entire world, in the whole field of scientific research. The only book of the kind which our own literature possesses is that production which is known as the “ Year-Book of Facts,” a volume which we need hardly add is absolutely worthless as a scientific record. The present American work is got up on a larger scale; and is, so far as selection Of paragraphs is concerned, edited with a certain selective skill, which renders it much more valuable as a scientific volume. But in saying this we are giving it all the praise within our power. For most assuredly it is unrepresentative, as of course every such volume must be. It is, as a matter of course, interesting to the mere “ dabbler ” in science; and we doubt not there are sufficient of this class alone in America to render its publication successful; but as a. purely scientific book it has no real value whatever. Let us take an example in order to prove the force of what we say. Chemistry alone is not one of the most widely diffused branches of knowledge, yet the monthly journal which is published by the “ Chemical Society,” and which consists almost exclusively of condensed paragraphs 'showing the work that is being done, would in two Of its numbers fully equal in bulk the present volume. That is to say, the progress of chemical science alone, in a single year, would, if recorded, occupy six times the space that is covered by the present work. When, then, we take the numerous other branches of science into consideration—such, for instance, as Anatomy, Physiology, Botany, Zoology, Geology, Palaeontology, Mineralogy, Physics, Mechanics theoretical and practical, Astronomy, Ethnology, Meteorology and Microscopy—we see how utterly impossible is such a book as the present one if it really be intended as a record of science for the scientific worker. If, on the other hand, it is addressed, as is our own brief summary, to the man of general scientific tastes, then we must regard it as a very excellent volume ; and most probably it is in this light that the editor, Mr. Spencer F. Baird, views the work. Examined under this aspect
" “Annual Record of Science and Industry,” for 1872. Edited by S encer F. Baird, with the Assistance of Eminent Men of Science. New
ork: Harper Brothers, 1873.
VOL. XII--——NO. XLIX- D D