A CONTRIBUTION TO THE ANATOMY AND PHY- 

 LOGENY OF AMPHIUMA MEANS (Gardner).^ 



ALVIN DAVISON, M.A. 

 Fellow in Biology, Princeton College, N. J., U.S.A. 



The anatomy of the adult skull of this eel-like Amphibian 

 has been well described by Wiedersheim (i). Osborn (8) has 

 given a most excellent description of the central nervous sys- 

 tem. Hay (2) has given an interesting account of the finding 

 of its eggs in an Arkansas swamp in September of 1887, and 

 subsequently published the results of his study of the embryos 

 contained in these eggs, and also of the skull of a small speci- 

 men six inches long. Cope has furnished a general description 

 of the species, and endeavored to trace out its phylogeny by 

 means of the insufficient data at hand. Kingsley (5), through 

 a study of Hay's embryos, for the most part confirmeyd the 

 latter's account, and also added to our sparse knowledge some 

 important points, especially along the line of phylogeny. The 

 writer has published a description of the conical arrangement 

 of the muscles (6), and in a later article the manner of the fer- 

 tilization of the eggs (7). No other investigations of any im- 

 portance than the above mentioned have been made on this 

 -peculiar Amphibian, owing undoubtedly to the fact that the 

 embryological material is so difficult to secure. The animals 

 will not breed in captivity, and the batches of eggs laid are so 

 few and so well concealed as to escape the sharp eye of the 

 naturalists. Since the eggs are fertilized internally, a com- 

 paratively short period of external incubation is necessary, 

 thereby limiting the probability of being discovered. Previous 

 to February, 1894, no one had secured a specimen of the 

 young less than six inches in length. In that month I was so 



1 I was very materially aided in making these investigations in the Princeton 

 Biological Laboratory by Mr. C. W. F. McClure who placed at my disposal a 

 large number of Amphibians and gave me numerous valuable suggestions. 



