26 Bulletin Wisconsin Natural History Society. [Vol. 9, Nos. 1-2. 



of body, with large broad head and rapidly tapering body. In 

 some cases there can be no doubt as to the species, there being 

 no other in the locality. A. punctatum, on the contrary, has a nar- 

 row head and long slender body, more like the adult. Some of 

 the variations of A. tigrinum figured by Powers look to me almost 

 exactly like normal specimens of A. punctatum. With respect to 

 body form, A. jeffersonianum is intermediate between A. tigrinum 

 and A. punctatum. 



The color of A. punctatum larvae varies considerably with the 

 habitat, being very dark in shaded pools containing dead leaves 

 and much organic matter in solution ; lighter in more open situa- 

 tions. In a larval specimen, presumably A. punctatum. cap- 

 tured August 2, 1906. a row of sharply defined small light spots 

 occurs along the upper part of the sides of the body, very much 

 as in the adult though situated not quite so far dorsally. In a 

 larval specimen, presumably A. jeffersonianum, taken from 

 Branchipus Pond on June 14, 1909, the row of four or five large 

 dark spots on the sides of the body, noted in the earlier stages, 

 was still clearly defined. 



In all the late larval stages examined the external gills were 

 in a well-developed condition, showing no signs of the degenera- 

 tion accompanying the metamorphosis. Some young post-larval 

 specimens of A. punctatum (see Plate II, Fig. 3), captured in 

 April, 1909, were not much larger than the largest larvae observed 

 in August, hence were probably one year old. 



I have refrained from figuring these later stages, since their 



identity has not been established beyond the possibility of a doubt 



by rearing them from the egg. 



Zoological Laboratory, University of Wisconsin. 



January, 1911. 



LITERATURE CITED. 

 Clarke, S. F. 



1879. The Development of Atnbystoma punctatum. Studies from 

 the Biological Laboratory of Johns Hopkins University. 

 Hay, O. P. 



1891. Batrachians and Reptiles of the State of Indiana. Seven- 

 teenth Annual Report of the Department of Geology and 

 Natural Resources. 



