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Show 1894,] ON THE TADPOLE OE XENOPUS LJEV1S. 101 EXPLANATION OF PLATE XII. Referenoe letters:-a.h., haemal arch ; a.n., neural arch ; c, vertebral body ; synostosis. The small numerals indicate the vertebrae (or, where two occur, the intervertebrae) which form the vertices of the curves. Fig. 1 a. Sole. Vertebral column with five sinuations. From the left side. § nat. size. 1 b. The same. Lines of curvature. 2. Sole. Line of curvature of a backbone with three sinuations, and a feeble fourth one posteriorly. R. C. S. 364. f nat. size. 3 a. Perch. Line of curvature of the backbone (with three sinuations), with contour of the animal's body in relation to it. R. C. S. 364. ^ nat. size. 3 b. The same. Curvature, enlarged for comparison with \b and 2. § nat. size. 4 a. Sole. Portion of a backbone with curvature involving vertebrae nos. 30 to 35, with marked angulation of those posterior to them, § nat. size. 4 b. The same specimen. First five vertebra?. X 2. 5. Sole. Portion of a vertebral column with vertebrae nos. 14 to 18 compressed and co-ossified. § nat. size. 6. Sole. Portion of a vertebral column, with vertebras nos. 23 to 34 compressed. R. C. S. 500. f nat. size. R. C. S. and the accompanying numbers refer to the ' Descriptive Catalogue of the Teratological Series in the Museum of the Royal College of Surgeons of England,' ed. 1893 ; and the specimens depicted in figs. 4 & 5 have been presented to that Institution by Prof. Sutton, but not yet catalogued. 2. Notes upon the Tadpole of Xenopus lavis (Dactylethra capensis). By FRANK E. BEDDARD, M.A., F.R.S., Prosector to the Society. [Received February 6, 1894.] (Plate XIII.) During the past summer one of the specimens of Xenopus Icevis at the Society's Gardens deposited a quantity of ova, which duly hatched out. Ultimately a few frogs were bred from the tadpoles. I preserved a series of tadpoles from the newly-hatched larva onwards, partly in corrosive sublimate and partly with Perenyi's fluid; the following notes refer to my examination of those specimens. But, before proceeding to describe the external and a few of the internal characters of the tadpoles, I will briefly direct attention to previous work upon the subject. The earliest description of the larva known to me is by the late Dr. J. E. Cray \ a description which was subsequently2 expanded and illustrated. The figure of the tadpole, showing the tentacles, does not show the dorsal fin, and is in other respects not good. In the definition of the tadpole (described as a distinct genus Silurana) we find the remark : " belly and underside of the 1 " Notice of a new Genus (Silurana) of Frogs from West Africa," Ann. Mag. N. H . (3) «xiv. p. 315. 2 " Note on the Clawed Toads (Dactylethra) of Africa," P. Z. S. 1864, p. 458. |