148 



BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



Color. — Over a v,'hite background the body is slightly greenish and 

 translucent, the color not evenly diffused but confined chiefly to the 

 central and lower portions of the body. A spot of dingy yellow near 

 the head, another in the caudal segments, and sometimes a third near 

 the center. The tAvo elongate oval eye spots, close together and some- 

 times apparently touching, near the anterior margin of the head, 

 are jet black. Back of them on the ventral surface between the 

 bases of the first antennae is a large transversely ellijDtical spot of 



Figure 100. — Labidocera aestiva: a. Female, dorsal ; b, male, dorsal ; c, male, 

 right first antenna ; d, e, male, fifth legs ; f, female, fifth leg. (From W. M. 

 Wheeler) 



a deep claret color, appearing black in certain lights. This is the 

 ventral eye and forms a raised prominence on the ventral surface 

 of the head. The first antennae are perfectly transparent, but show 

 a faint bluish tint by transmitted light. The mouth parts also 

 sometimes show a similar bluish tint. (Rathbun.) 



Female. — Head evenly rounded anteriorly; corners of fifth seg- 

 ment symmetrical, reaching the center of the genital segment; 

 urosome 2-segmented, symmetrical, the genital segment much longer 

 than the abdomen, its sides covered with short hairs; caudal rami 

 two and one-half times as long as wide ; fifth legs symmetrical, rami 



