298 INEZ WHIPPLE WILDER. 



The larvae frequent the quieter regions, always out of the 

 current except when a temporary disturbance drives them into it. 

 They seek not only quiet but very shallow water, where they lie 

 motionless among the decaying leaves, which, owing to the 

 wooded nature of their habitat, fill such pools. Such leaves also 

 furnish quiet lurking places when they lie in a thick mass covering 

 the surface of the more rapidly moving regions of the stream. 

 Among the loose debris and sediment which these surroundings 

 afford, the larvae lie, their mottled brown color forming a perfect 

 protective resemblance. The collector may thus at first stare 

 several minutes into such a little pool before he recognizes in an 

 apparent fragment of the midrib of a decaying leaf, the mid- 

 dorsal ridge of a Desmognathus larva, and he may possibly realize 

 the true nature of the object under observation only when upon 

 disturbing the water, active swimming movements betray the 

 living animal. On the other hand having once begun to recog- 

 nize the larvae one is frequently deceived into picking up some 

 lifeless fragment which the larvae so closely resemble. Several 

 larvae are frequently found in close proximity in the same little 

 pool or mass of leaves, a fact which probably results from the 

 abundance of the larvae, but may in the early fall be due to the 

 simultaneous arrival, in the same little pool, of several individuals 

 of the same brood. 



Frequently the larvae, when concealing themselves among the 

 leaves, lie half out of the water, the body immersed just suffici- 

 ently to bring the gills under the surface. This habit I have 

 observed particularly in the case of individuals in captivity, and 

 have thought that it might be associated with lack of sufficient 

 oxygen. However the larvae are certainly not adapted to the 

 pressure conditions of deep water, and although they are quiet 

 and apparently comfortable when in captivity in water a centi- 

 meter deep, if the depth of the water be gradually increased they 

 show signs of uneasiness when it becomes about two centimeters, 

 and by the time a depth of three or more centimeters is reached 

 they make frantic efforts to reach the top of the water, where, 

 however, they can sustain themselves only by active swimming 

 or by resting upon some surface. In fact under these conditions 

 they almost invariably swim to the edge of the aquarium, run 



