622 THE CHEIROPTERYGIUM. 



This view of the cheiropterygium corresponds in some respects with that 

 put forward by Gotte as a result of his investigations on the development of 

 the Urodele limbs, though in other respects it is very different. A difficulty 

 of this view is the fact that it involves our supposing that the radial edge of 

 the limb corresponds with the metapterygial edge of the piscine fin. The 

 difficulties of this position have been clearly pointed out by Huxley, but the 

 fact that in the primitive position of the Urodele limbs the radius is ventral 

 and the ulna dorsal shews that this difficulty is not insuperable, in that it is 

 easy to conceive the radial border of the fin to have become rotated from its 

 primitive Elasmobranch position into the vertical position it occupies in the 

 embryos of the Urodela, and then to have been further rotated from this 

 position into that which it occupies in the adult Urodela and in all higher 

 forms. 



BIBLIOGRAPHY of the Limbs. 



(477) M. v. Davidoff. "Beitrage z. vergleich. Anat. d. hinteren Gliedmaassen 

 d. Fische I." Morphol. Jahrbuch, Vol. v. 1879. 



(478) C. Gegenbaur. Untersuckungen z. vergleich. Anat. d. Wirbelthiere. 

 Leipzig, 1864 5. Erstes Heft. Carpus u. Tarsus. Zweites Heft. Brustflosse d. 

 Fische. 



(479) C. Gegenbaur. "Ueb. d. Skelet d. Gliedmaassen d. Wirbelthiere im 

 Allgemeinen u. d. Hintergliedmaassen d. Selachier insbesondere." Jenaische Zeit- 

 sckrift, Vol. V. 1870. 



(480) C. Gegenbaur. " Ueb. d. Archipterygium." Jenaische Zeitschrift, Vol. 

 vii. 1873. 



(481) C. Gegenbaur. "Zur Morphologic d. Gliedmaassen d. Wirbelthiere." 

 Morphologisches Jahrbuch, Vol. II. 1876. 



(482) A. Gotte. Ueb. Entivick. u. Regeneration d. Gliedmaassenskelets d. Molche. 

 Leipzig, 1879. 



(483) T. H. Huxley. "On Ceratodus Forsteri, with some observations on the 

 classification of Fishes." Proc. Zool. Soc. 1876. 



(484) St George Mivart. "On the Fins of Elasmobranchii." Zoological 

 Trans., Vol. x. 



(485) A. Rosenberg. "Ueb. d. Entwick. d. Extremitaten-Skelets bei einigen 

 d. Reduction ihrer Gliedmaassen charakterisirten Wirbelthieren." Zeil.f. iviss. Zool., 

 Vol. xxin. 1873. 



(486) E. Rosenberg. "Ueb. d. Entwick. d. Wirbelsaule u. d. centrale carpi 

 d. Menschen. " Morphologisches Jahrbuch, Vol. I. 1875. 



(487) H. Strasser. "Z. Entwick. d. Extremitatenknorpel bei Salamandern u. 

 Tritonen." Morphologisches Jahrbuch, Vol. V. 1879. 



(488) G. 'S wirski. Untersitch. iib. d. Entwick. d. Schultergitrtels u. d. Skelcls d. 

 Brustflosse d. Hechts. Inaug. Diss. Dorpat, 1880. 



(489) J. K. Thacker. "Median and paired fins. A contribution to the history 

 of the Vertebrate limbs." Trans, of the Connecticut Acad., Vol. ill. 1877. 



(490) J. K. Thacker. "Ventral fins of Ganoids." Trans, of the Connecticut 

 Acad., Vol. iv. 1877. 



