i;:4 NEW JERSEY AGRICULTURAL COLLEGE 



the large claw with a median prong and a small, tooth-like process at 

 its base, the small claw very short and simple. The claws of the mid 

 and posterior tarsal joints are equal and simple, the latter somewhat 

 smaller than the median. 



Description of the Larva. 



The larva in general appearance resembles the other species of 

 the genus which occur in New Jersey, but is easily separated from all 

 by the very dark head; it is further st^parable from piinctipennis and 

 viacuUpcnnis by the anal gills, which are even shorter than in crucians. 



The full-grown larva measures 6 mm., or .'?4 of an incli in length. 

 The head is dark brown with a single black diffused spot in the center 

 of the vertex and a pale yellow circle around the eyes. The antenna? 

 (Figure 2 e) is two-jointed, the first joint broader than long and 

 fixed immovably ; the second is much longer and narrower, almost 

 straight, tapering toward the apex, tenninated by three pegs of uni- 

 form length and two long, simple, flexible bristles; in color it" is 

 evenly dark brown with the apical articulations pale yellow. Appar- 

 ently, there is no tuft or divided hair on the shaft of this second joint 

 and no tubercle or pit in indication of one. The mentum (Figaire 2 h) 

 is triangular in form, almost as broad as long, with an apical tooth 

 and five others on each side. The mandible (Figure 2 d) is elongate, 

 with three large and several small teeth and a comb-like structure at 

 the apex ; ' on the dorsal stirf ace is one long, slender, simple spine, a 

 stouter one with short bristles, and a large, weakly-chitinized, com- 

 pound spinet. The maxilla (Figure 2 c) is a pale yellow, squarish 

 structure, with a thick tuft of short hairs at the apex and patches of 

 hair irregttlarly distributed over the surface ; its palpus is dark brown, 

 almost three times as long as its greatest width, with three yellow, 

 apical pegs and a small tuft of two or three branched hairs arising 

 from a pit near the apex. The triangular plates, one on each side of 

 the respiratory apparatus on the eighth segment, each bear thirteen or 

 fourteen long teeth of almost even length on the posterior margin, and 

 each tootli has three or four minor teeth at the base. The tracheal 

 gills are slightly inflated, pointed and about one-fourth the length of 

 the r.inth segment. 



