122 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



admits this for one plexus, but not for the other. In 

 particular I would draw attention to Miss Sweet's fig. 2 

 (p. 282), drawn up to show the transference of the cruralis 

 fibres from the ixth to the viiith nerve, a series which 

 I think, does not appear to be a very natural one, or to 

 support the method on which it is based. The works of 

 these two authors have cleared up so many points that I 

 have ventured to draw attention to what appears to me 

 this one defect in their work. 



I am greatly indebted to my valued friend, Mr. A. W. 

 Kappel, Librarian to the Linnean Society, and also to 

 Prof. G. B. Howes, F.R.S., for help with the literature. 



LITERATURE. 



1. Adolphi, H. — " Uber Variationen der Spinalnerven und der 



Wirbelsaule aimrer Amphibien. I. (Bufo variabilis, Pall.) " 

 Morph. Jahrb. Bd. xix., pp. 313-375. Taf. xii. 1893. 

 cp. especially fig. 4. 



2. Adolphi, H. — Ibid. "II. (Pelobates fusc-ws, Wagl. und Rana 



cscidcnta,~L.)" M. J. Bd. xxii., pp. 449-490. Taf. xix. 

 1895. cp. figs. 10 and 11. 



3. Adolphi, H. — Ibid. "III. {Bufo cinereus, Schneid.)." INI. J. Bd. 



xxv., pp. 115-142. Taf. viii. 1898. cp. fig. 11. 



4. Adolphi, H. — " Uber das Wandern dor Extremitatenplexus und des 



Sacrum bei Triton taeniatus." op. cit., pp. 544-554. 1898. 



5. Bateson, W. — " Materials for the study of variation." pp. 129-145. 



London. 1894. Valuable summary, with figures, of works 

 on variation of spinal nerves of Vertebrates, including Pipa. 



6. *Benham, W. B. — "Notes on a particularly Abnormal Vertebral 



Column of the Bull-frog (Rana mugiens) ; and on certain 

 other variations in the Anuran Column." Proc. Zool. Soc, 

 1894, p. 477. 1894. 



7. *Boukne, A. G. — " Certain abnormalities in the common Frog (Rana 



temporaria)." Q.J. M.S. N. S. Vol. xxiv., p. 83. 1884. 



