552 THE STUDY OF INSECTS. 



The family Malachiid^ (Mal-a-chi'i-dae) is composed 

 chiefly of small or very small beetles, found on flowers, and 

 on the ground near water. They vary greatly in form ; but 

 bear a general resemblance in structure to the preceding 

 family, from which they can be distinguished by the presence 

 of only six ventral abdominal segments. Some members of 

 the family are furnished with soft, orange-colored vesicles 

 which they protrude from the sides of the body, and 

 which are supposed to be scent organs for defence. "jKj" 

 One of our most common representatives is Collops ' ' 

 quadrimactilatus (CoFlops quad-ri-mac-u-la^tus), which '^- ^^o- 

 is yellowish orange, with the top of the head and four spots 

 on the wing-covers bluish black (Fig. 670). 



Family Clerid^E (Cler'i-dae.) 

 The Checkered Beetles. 



The family Cleridae includes a considerable number of 

 species which are found on flowers and on the trunks of 

 trees. Many of them are beautifully marked with strongly 

 contrasting colors; this has suggested the common name 

 checkered beetles for them. Frequently they are more or 

 less ant-like in form, the prothorax being in these cases 

 narrower than the wing-covers, and slightly narrower than 

 the head. The abdomen has either five or six ventral seg- 

 ments; the anterior coxae are conical, prominent, and con- 

 tiguous, or very slightly separate ; the hind coxae are trans- 

 verse, not prominent, and covered by the femora in repose ; 

 the legs are slender ; and the tarsi are five-jointed. 



In the larval state these insects are usually carnivorous, 

 living under bark and in the burrows of wood-boring insects, 

 upon which they prey; some are found in the nests of bees ; 

 and still others feed on dead animal matter. 



Figure 671 represents one of our more common species, 

 Trichodes nuttalli (Tri-cho'des nut-tal'li). 



