THE NESTS AND LARV.E OF NECTURUS. 



The ground color of the dorsal and lateral surfaces is a dark 

 brown, with small scattering spots of lighter color especially 

 noticeable along the sides of the body and tail. As compared 

 with the earlier stages the pigmentation is much more intense, 

 but this merely serves to accentuate the light-yellow stripes. 

 It is to be particularly noted that in all the western larvae that I 

 have examined, the dark color of the dorsal surface of the body 

 is continued along the dorsal edge of the tail between the lateral 

 stripes (see Fig. 4). The ventral surface is pale yellow, almost 

 transparent. 



FIG. 4. FIG. 5. 



FIG. 4. Caudal portion of a 34-mm. Neclurus larva taken from the Detroit 

 River, showing color pattern of the tail. The specimen is somewhat shrivelled 

 from partial drying before preservation; in particular the ventral margin of the tail 

 is upturned. Photographed after preservation in formalin. (X 3M-) 



FIG. 5. Caudal portion of a 35-mm. larva of Necturus taken from a stream in 

 northwestern Pennsylvania, showing color pattern of the tail. Photographed from 

 a formalin specimen. (X 3/^.) 



Mention has already been made of larvae taken from a stream 

 habitat in northwestern Pennsylvania. No attempt was made 

 to capture all the specimens found, but a series was preserved 

 representing a gradation in size from the smallest, 35 mm. long, 

 to the largest, 20 cm. in length. Of these the fourteen smallest, 

 all under 15 cm. in length, show larval characteristics in the 

 color pattern. 



The smallest specimen, 35 mm. in length (see Fig. 6), was 

 taken on September 13, 1906. This larva is younger and mor- 

 phologically less advanced than the slightly smaller larva ob- 

 tained from the Detroit River; but on account of an important 

 difference in the color pattern its description has been deferred. 



