584 



THE STUDY OF INSECTS. 



a. ivj. 7 



the body and discharging an oily fluid from it. They present 

 an absurd appearance, walking off clumsily, 

 and carrying the hind end of the body as high 

 as possible. The most common species are 

 large, smooth, club-shaped beetles (Fig. 712), 

 and are commonly known as Pinacate-bugs. 

 These beetles and those belonging to several 

 closely allied genera are wingless. 



The family ^GIALITID^ (^-gi-a-lit'i-dae) 

 was founded upon a single species from Alaska; 

 recently another has been found in California. 



The family ClSTELID^ (Cis-teri-dae) in- 

 cludes about fifty North American species, some of which 

 are quite common. These are brownish beetles, without 

 spots, which are found on leaves and flowers and under bark. 

 The body is usually elongate, elliptical, and quite convex. 

 They are most easily distinguished from allied families by 

 the tarsal claws being pectinate, and the anterior coxal cavities 

 closed behind. The larvae of some of our species at least live 

 in rotten wood and resemble wire-worms in appearance. 



The family Othniid^ (Oth-ni'i-dae) is represented in our 

 territory by four species of Othnius (Oth'ni-us), one from 

 the East and three from the far West. They are small 

 beetles, which are found running actively on the leaves of 

 trees, and are probably predaceous. In this family the an- 

 terior coxal cavities are closed behind, and none of the ab- 

 dominal segments are grown together on the. ventral side. 



The family Lagriid^ (La-gri'i-dae) includes only five 

 North American species, all of which are from the East, and 

 are found under bark and on leaves. They are elongate 

 beetles, with a narrow, subcylindrical prothorax, and 

 a more or less brassy color. Our most common spe- 

 cies is Arthroniacra cenea (Ar-thro-ma'cra ae'ne-a). 

 This species is nearly half an inch in length (Fig. 713). 



The family MONOMMID^ (Mo-nom'mi-dae) is rep- ^'''- ^'3- 

 resented in this country by a single genus, including four 



