72 Bulletin American Museum of Natural History [Vol. XLII 



varied from five to eight, and ten days were required for eggs laid in the 

 aquaria on May 12 to hatch. It is possible to obtain larvae during nearly 

 the whole year, if the aquarium is well stocked with adults. Records 

 show them to be present from April to October, inclusive, besides during 

 February. A number of fairly well-grown larvae were found under a 

 stick in a moist situation on May 28. As pupae were observed during the 

 middle of July, the larval period is probably of about two months' 

 duration. 



Egg-cases. — Case, without its filament, nearly round and varies in size, as does 

 the filament. The ease proper averages 1.13 mm. in width and 1.08 mm. in length; 

 and the filament, 0.44 mm. in width at its base and 3.47 mm. in length. The top of the 

 egg-case tends to be slightly flat and the cap is continuous with the filament, forming a 

 slight cavity at the base of the filament, which tapers slightly towards its tip and is 

 flat and ribbon-like. 



Newly Hatched Larva. — Length, 1.67-1.93 mm.; width, 0.296 mm. Whitish, 

 except chitinized portions which are yellowish; integument, including thoracic 

 sclerites, dotted with minute setae which arise from microscopic tubercles. 



Head quadrangular, very slightly elevated; fronto-clypeal suture weakly in- 

 dicated, more prominent at the sides; frons somewhat campanulate, its rounded 

 posterior end attaining the caudal margin of the head so that there is no epicranial 

 suture and the postfronto-vertical sclerites do not meet; gula pentagonal, and the 

 gular sutures prominent and confluent; two small, horizontal, elongate, cervical 

 sclerites present. 



Labro-clypeus with its anterior margin nearly in line with the lateral expansions 

 of the epistoma, quadridentate and possessing a row of four seta?. Left expansion 

 slightly more prominent than the right, both rounded and bearing a few short seta?. 

 Epipharynx spinous. 



Ocular areas in groups of six and indistinct, arranged somewhat in a circle; the 

 first three equidistant and with their axes nearly vertical, while the other three have 

 their axes nearly horizontal. 



Antennae fairly short, barely exceeding the distal inner tooth of the mandible; 

 first segment nearly equal to the second in width, a little longer and slightly con- 

 stricted; second segment swollen somewhat in the middle and bearing a colorless, 

 finger-like appendage, in addition to the sense-cones at the latter's base; third segment 

 the same length as the appendange of the second segment, about twice as wide and 

 long as the second segment, and bearing at its extremity several sense-cones and 

 several long setae. 



Mandibles symmetrical, fairly prominent, sharply pointed at their tips and with 

 three strong inner teeth, the anterior two about the same size and larger than the 

 small basal tooth; molar areas smooth. 



Maxillae with joint-like palpifer; stipes large, swollen, slightly narrowed towards 

 the apex, longer than the palpifer and palpus together, its inner surface provided with 

 a row of five stout setae, and two lateral slender setae on its distal half, one placed 

 behind the other; palpifer fairly large, about the same width as its palpus, nearly as 

 wide as long, bearing a single, stout, inner, lateral seta near its base and a rudimentary 

 lobe, possessing apical setae; first segment of palpus about the same length as the 

 rudimentary lobe of the palpifer and equal to the second in length and width, while 



