54 OUTLINES OF ENTOMOLOGY. 



medium or rather small size (three- fourths inch and under in length), of 

 elegant form and often of brilliant metallic color. Their chosen haunts 

 are sunny path-ways, hard beaten roads and the sandy shores of streams, 

 lakes and the ocean. 



The head of a Tiger- beetle is broader than the thorax. It is pro- 

 vided with a very complete mouth, of which the most important parts 

 are the long, sharply-toothed and curved jaws, which cross each other 

 when closed. The eyes are large, round or somwhat oblong and pro- 

 truding ; the antennae long and slender, arising from the face just above 

 the base of the mandibles. The prothorax is nearly square, the scutel- 

 lum very small, and the wing cases, which are rather narrow, widen 

 slightly toward the hinder end of the body. The under wiugs are well 

 developed, and the insect rises easily into the air for short flights. The 

 legs are long and slender and the joints of the feet spiny. The dark 

 metallic color is in some species varegated by dots and zigzag lines of 

 yellow or cream white. The larvae live in perpendicular holes in the 

 ground and are extremely ugly in appearance. They have a broad head 

 and immense jaws, and long sprawling legs. On the middle of the 

 back is a large double hump, terminating in backward curving hooks, 

 of which these creatures make use in climbing to the entrance to their 

 holes and sustaining themselves there while lying in wait for their prey. 

 Any unlucky insect happening to stray within reach of those terrible 

 jaws is seized with a grasp from which there is no escape, dragged into 

 the hole and devoured. 



More than sixty species of Cicindelidce are found in the United 

 States. (See beetle on plate.) 



The Ground-beetles or " Caterpillar-hunters " include a great num- 

 ber of predaceous species, which may occasionally be seen running 

 over the ground in fields and gardens, but are usually hidden under 

 stones, boards, fallen leaves and the like during the day. They are 

 easily distinguished from the Tiger-beetles by the head being narrower 

 than the prothorax, and the latter somewhat more constricted or taper- 

 ing toward the base of the wing covers. They are also, with a few 

 exceptions, of plainer coloring, and the most conspicuous species are 

 of larger size than is the rule among the Tiger-beetles. One of the 

 chief structural characters of these beetles is the peculiar eardrop- 

 shaped trochanter of each of the hinder legs. (See Part 1st, Fig. 6, 

 A, b.) 



They are, as rule, nocturnal in their habits, running out of their 

 hiding places at nightfall, and exploring field and garden, even climb- 

 ing trees in the search for their six-legged game, tearing in pieces cater- 

 pillars and grubs, and even other beetles, wherever found. They are often 



