36 BERTRAM G. SMITH. 



ternal gills are retained, though evidently in a somewhat degen- 

 erate condition. The legs are well developed. The mouth 

 opening is terminal, not ventral. The tail is proportionally 

 smaller than in specimens ten weeks old ; the ratio of length of 

 tail to entire length is 1 : 2.5 in the case of the year-old larva, and 

 1 : 3 in the ten-weeks' .larva. The body is plump as compared 

 with the adult, the somites show distinctly, and the lateral folds 

 are very slightly developed. There is a conspicuous gular fold 

 not present in the adult. The color of the dorsal and lateral sur- 

 faces is a very dark brown," almost black, so that the irregular 

 black spots which are present do not show in the photograph. 

 After preservation in formalin the ground color becomes lighter 

 and of a bluish tint, and the black spots show more distinctly. 

 A few scattering inconspicuous yellow spots are also present. 

 The ventral surface is considerably lighter in color. 



These larvae are more active than the adults, and are extremely 

 sensitive to shocks and jars. They were never observed to come 

 to the surface for air. 



The Tzvo-year-old Larva. — (See Fig. 13.) Two specimens 

 were found, measuring respectively 12 cm. and 12.3 cm. These 

 differ from the year-old larvae in the small size of the external 

 gills, in the absence of the gular folds, the slightly greater develop- 

 ment of the lateral folds, and in the absence of visible somites, 

 though the lateral folds are metamerically notched. The ground 

 color is a trifle lighter, so that the black spots are more clearly 

 seen ; less conspicuous yellow spots are also present. No stages 

 intermediate between these and the 7 cm. larvae were obtained, 

 and it seems probable that they represent the second year of 

 larval development. 



One of these specimens ate, soon after being captured, a large 

 Corydalis larva. Another specimen, when placed in quiet water, 

 regurgitated a partly digested 6 cm. larva of its own kind. 



As in the younger stages, these specimens were not observed 

 to come to the surface for air ; however, the evidence on this 

 point is not conclusive. 



