SIALIDiE. 



605 



tula quadrimacAdata Linn. (Fig. 588) is reddish yellow, with 

 four dark clouds on the wings which are yellow anteriorly on 

 the base. In Diplax the abdomen is a little shorter than the 

 wings, and is slender, 

 flattened, compressed at 



the base, while the feet ^^^^^^^044^^^ 

 are long and slender. 

 Diplax rubicundula Fabr. 

 is a very abundant spe- 

 cies, being yellowish red. 

 Dix>lax Berenice Drury 

 (Fig. 589, male; fig. 590, 

 female) is black, with the Fig. 5oi. 



head blue in front, spotted with yellow, while the thorax and 

 abdomen ai*e striped with yellow. There are fewer stripes on 

 the body of the male. D. Elisa Hagen (Fig. 591) is black, 



with the head yellowish and 

 with greenish j'ellow spots 

 on the sides of the thorax 

 and base of the abdomen. 

 The Nannophya hella of 

 Uhler (Fig. 592) is a smaller 

 form, with an unusually 

 short abdomen, and the 

 reticulations of the wings 

 ^'^^- 5^- are large and simple. It is 



black, while the male is frosted over with a whitish powder. 



SiALiD^ Leach. This family is not a numerous one, but the 

 species are interesting as comprising some of the largest of in- 

 sects. Hagen defines the group briefl}- 

 as having the body short and thick, 

 while the prothorax is large and square. 

 The antennae are long and setaceous ; 

 the wings are large, reticulated, the pos- 

 terior ones with the anal space plicated, 

 and the tarsi are five-jointed. F'^- ^^• 



"The female of Sialis," according to "Westwood, "deposits 

 an immense quantity of eggs, which she attaches one by one 



■£.y. 



