AN INTRODUCTION TO EN TO:.. 



DD. Antenna; 5-jointed.* 



E. Lateral margin of scutellum with a furrow in which the edge of 

 the wing-cover nts when closed. 

 F. Scutellum nearly flat, attenuated posteriory. 

 G. Tibiae unarmed or furnished with very fine short spines. 



XXXIII. Pi M AloMlDvE. 



Tibiae armed ng spines in t 



Fam. XXXIV. CM> 

 IT. Scutellum very convex, covering nearly the whole abdomen. 



Fam. XXXV. COKIMI LA N 



EE. Lateral margin of the scutellum without a fun Hum 



very convex, covering nearly the whole abdomen. 



Fam. XXXVI. Si U i i LLERIDA 



o. .V- FIG. 151. Am- FIG. 15,2. c'.i/- FK.. 153. Pyr- Fie;. 154- Lygt~ FIG. i. C*- 

 tidtr. tkocffrimr. sitttr. rkocoridee. idtr. retJte. 



Family XL CORlsiD/E.f 



( Water-boatmen?) 



To the Corlsidie belong certain aquatic Hctt ropier a which are 

 very widely and commonly distributed throughout our country. 

 They are of medium or small si/.e, and of somewhat elongated oval 

 form. They occur in lakes, ponds, and streams, in both stagnant 

 and running water, and even in the salt lakes of Utah and Califor- 

 nia. 



All of the North American species of this family belong to the 

 genus Corisa. Fig. 156, which represents a 

 ^_^ species of Corisa % illustrates the form of the 



rT3 body. These insects may be distinguished by 



^^^Bjl the peculiar tarsi of the front legs. These 



jjfT ^^\ lars ' ' uv ! ^ ltl( ' lu ' ( l or scoop-like in form; each 



"lE?' Consists! a single- -r-mcnt, and bears acomb- 



^ - like fringe of bristles. Tin structure of the 



./ Iu-ad of tlu-sf insectfl is (juite unusual. In- 



FIC. 156. Corita unduiata. stead of being inserted in the prothorax. tin- 

 head overlaps that segment. The position of 

 the mouth-parts is also peculiar ; these are pushed through an op 



* In certain families there are minute intermediate joints between the prim ipal joints 

 of the antennae ; for the purposes of this table, these intermediate joints arc nut iuntrcl. 

 f Corlsida, Corisa: coris (KopiS), a bug. 



