264 NEW YORK STATE MUSEUM 



appeared entirely unfitted to capture insects or take solid food.^ 

 The undeveloped -condition of the limbs at the time of hatching 

 gives evidence of the helpless condition of the larvae, particularly 

 when they are not in an aquatic environment. Inez W. Wilder 

 ('13) found newly hatched larvae of D . fuscus very active and 

 able to crawl about; certainly the young of Hemidactylium are 

 incapable of doing this when reared under laboratory conditions. 

 The aquatic larval period ofD. fuscus perhaps necessitated the 

 early full development of limbs to enable them to reach thq water. 

 Conversely, the absence of an aquatic condition in Hemidactylium 

 may account for the lack of such development although the necessity 

 of being able to capture food remains. 



Pigmentation of the integument, as observed in the development 

 of Hemidactylitmi, has three distinct phases. The earliest indication 

 of color appears as thin wash of pigment more or less regularly 

 distributed. In the second stage the pigment is in irregular flecks 

 confined mostly to the dorsal surface of the body. By spreading 

 and uniting the color pattern is developed in the third stage. 



The length of time the gills are retained in larvae reared under 

 artificial conditions depends, to a considerable extent, upon the 

 moisture content of the moss in which they are kept. To determine 

 if possible the influence on development of such factors as light 

 and moisture, some experiments were conducted along the following 

 lines: In some specimens taken May 30th the embryos were supplied 

 with fully developed fringed gills, but still inclosed, June 12th, 

 within the gelatinous envelops. Of these eggs, two lots of about 

 a dozen each were placed in glass jars containing sphagnum moss, 

 supported by a wire screen placed an inch above the bottom of the 

 jar. Water in the jar insured a constant hiimid condition without 

 being in contact with the moss. 



On June 19th larvae were found free in the moss and adhering ' 

 to the sides of the jars. On June 21st, four specimens in jar i and 

 three in jar 2 were found in the water in the bottom of the jars 

 having worked their way through two and one -half inches of moss. 

 Of these seven specimens, but one was alive. On June 23d the 

 remaining specimens died without showing the slightest reduction of 

 gills. 



The fact that some larvae worked their wa}'- through the moss 

 and into the water probably has no significance. Several artificial 

 conditions imposed on the specimens used in the experiments have 

 no counterpart in nature, (i) To reach the water level in bogs, 



