THE STRUCTURE OF THE SPERMATOPHORES OF 

 AMBYSTOMA PUNCTATUM. 



BERTRAM G. SMITH. 



Since the recent paper of Wright and Allen ('09) has again 

 directed attention to the breeding habits of Amby stoma puncta- 

 tum, it has occurred to me that a more careful description of the 

 spermatophores than has yet been given might be of value in a 

 comparative survey of the habits of the urodeles. No adequate 

 figures of these spermatophores have yet been published. 



The spermatophores of Amhy stoma punctatum studied by me 

 at Ann Arbor (Smith, '07) were not freshly deposited, and were 

 not in the best possible structural condition for study; hence 

 only a brief description, illustrated by a photograph, was at- 

 tempted. Since then I have been able to study these structures 

 in abundance under the best possible conditions. As evidence 

 that the spermatophores were freshly deposited, there may be 

 cited the fact that the spermatozoa of some of them were found 

 to be active when examined in the laboratory seven hours after 

 their collection. The results of this study have confirmed the 

 description previously given by me, in regard to distribution and 

 general structure, but have revealed the common occurrence of 

 compound spermatophores, a condition previously unnoticed. 



In the early spring of 1909, when the snow had nearly all dis- 

 appeared, I found specimens of Ambystoma punctatum and A. 

 jeffersonianum, under rocks on the hillside near "Branchipus 

 Pond," about two miles from the campus of Syracuse University. 

 The study of the habits of these animals was undertaken in 

 order, if possible, to determine by direct observation the exact 

 procedure in the process of fertilization by means of spermato- 

 phores in the case of A. punctatum, and to obtain data in regard 

 to A. jeffersonianum, in which the manner of fertilization is 

 entirely a matter of conjecture. 



Conditions made it impossible to keep a very close watch of 

 the pond during the breeding season, and the abruptness of the 

 weather changes caused me to miss the few opportunities for direct 



204 



t 



