BEETLES. 361 



anterior projection of the prothorax, which shields the head, back to near the pos- 

 terior angles of the prothorax. 



Among the insects of the sub-family Lyeinas, of which the species are diurnal in 

 habits, and wander about plants in search of insect food, Calopteron reticulation may 

 be chosen as a representative. This species has the elytra gradually- 

 widening from the base to near the tip, and covered with a fine net-work 

 or reticulate surface ; its flat serrate antennas and its under surface are 

 black, as well as the middle of the prothorax, and the apical end of the 

 elytra. In the form which was once known as C. terminate, but which 

 is now regarded to be a variety of C. reticulation, the anterior two-thirds 

 of the elytra are yellow, while in other specimens there is a patch of Fm 

 black near the base of each elytron. These insects vary from 0.40 to 

 0.75 of an inch in length. Their larvas are clay-yellow, prettily marked 

 with black, and are found under logs and stones, where they eat other insect larvre. 



The ELATERIDJS, including with them the EUCNEMID.E and CEBKIONID^, which 

 are often regarded as distinct families, comprise considerably more than three thou- 

 sand species of described coleoptera, which are quite distinctly separated by a few 

 marked characters, of which the following is an abstract from Drs. Le Conte and 

 Horn's work, to which reference has been so often made : The antennas are usually 

 serrate, sometimes pectinate or flabellate, and are often inserted in grooves upon or 

 under the front ; the five (rarely six) ventral segments are free, and the first of them 

 is not elongate ; the hind coxaa are contiguous, and sulcate for the reception of the 

 thighs ; the front coxae globose, and contained entirely within the prosternum ; the 

 prothorax loosely articulated to the mesothorax, and the prosternum prolonged behind. 

 The greater part of the Elateridas are popularly known in America as snapping- 

 beetles and spring-beetles, and in England as click-beetles and skipjacks, because of 

 their power of jumping up into the air when placed upon the back. Dr. Le Conte 

 says this jumping " is effected by extending the prothorax so as to bring the prosternal 

 spine to the anterior part of the mesosternal cavity, then suddenly relaxing the muscles 

 so that the spine descends violently into the cavity, the force given by this sudden 

 movement causes the base of the elytra to strike the supporting surface, and by their 

 elasticity the body is propelled upward." Without the aid of this mechanism, these 

 short-legged beetles would find difficulty in regaining their foothold when they had 

 fallen on their backs, which might often occur, because of their habit of dropping to 

 the ground, with legs retracted and feigning death, upon the slightest disturbance. 

 If a beetle fails to regain his proper position by the first jump, the springs are repeated 

 until success results, each spring, especially if upon a hard surface, is accompanied by 

 a distinctly audible click. 



The habits of the Elateridae are quite diverse, many sit upon leaves of plants and 

 upon grass, others are abundant under bark, and many species live concealed beneath 

 stones. The larvae usually live in decaying wood; some of them, however, do not 

 confine their attacks to dead vegetable matter, but are known as seriously injurious to 

 living plants and to cultivated crops ; a few of these larvae are carnivorous, the larvae of 

 Drasterius amahilis, in the United States, being known to devour locusts' eggs. Many 

 elaterid larvae, because of their cylindrical form and very firm, smooth, chitinous 

 exterior, are known as wire-worms. The larvae have six legs, no ocelli, and their 

 antennae are very short and three-jointed. Wire-worms have sometimes destroyed 

 potatoes and cabbage roots by riddling them with their burrows. Some of these larvae 



