THE VPSILOID APPARATUS OF URODELES. 295 



vestiges of the ypsiloid musculature remain to indicate the former 

 possession of the apparatus. 



4. This interpretation of the function of the ypsiloid apparatus 

 throws some light upon the systematic position of certain of the 

 lower Urodclcs. The more obvious conclusions are : 



a. That forms with lungs but without vestiges of an ypsiloid 

 apparatus, and with no evidence of degeneration in the pelvic 

 region (e. g., Ncctunts) are neither degenerate forms, nor perma- 

 nent larvae of any of the Salamandrida. 



b. That the absence of the ypsiloid cartilage considered in con- 

 nection with the absence of lungs in the case of Typhlomolge is 

 in full accord with the conclusion [Emerson, 1905] that TypJilo- 

 tnolge is the permanent larva of some lungless salamander. 



c. That the presence of a functional ypsiloid apparatus in 

 Cryptobranchus indicates that Cryptobranchus lies near the line of 

 descent of the Salamandrida. 



SMITH COLLEGE, NORTHAMPTON, MASS. 

 February 1 , 1906. 



POSTSCRIPT. 



Since the above article was written, a paper on the Anatomy 

 of Cryptobranchus allegheniensis by Reese has appeared in the 

 American Naturalist, Vol. XL., No. 472. In this article the 

 following statement is made : 



" Anteriorly the pubis is prolonged into a long, cartilaginous 

 epipiibis, which, instead of being forked as in the Japanese sala- 

 mander and some other Amphibia, is a straight rod, slightly 

 broadened and flattened at its distal end and somewhat enlarged, 

 both laterally and dorso-ventrally at its attached end. The union 

 of the pubis and epipubis is a close one, but allows considerable 

 freedom of motion." 



The results of my own dissections (p. 264) are so completely 

 at variance with this description of Reese's that I can but feel 

 that he was mistaken in the form and character of the part in 

 question. I have, however, based my description upon three 

 specimens only, and it is possible that we have here to do with 

 a case of marked individual differences ; but that all of my speci- 

 mens should have the typical Y-form, while all of Reese's were 

 rod-shaped, does not seem probable. I. L. W. 



