BEETLES. 



361 



Fia. 412.— Calup- 

 teron reticii- 

 latum. 



rniterior jiroji^rtiim of tlu' jn-dtlinrrix, wlj'ich sliit'lds tbe Lead, back to near the pos- 

 terior angles of the prdthnrax. 



Ainoiii; the iiiseets of tlie sufi-fauiily Lyciiue, of whieh the si)ecies are diurnal in 

 habits, and wander about plants in search of insect food, Calojiteron retictilatinn may 

 be chosen as a representative. Tins s]iecies has the elytra gradually 

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

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

 black, as well as the nnddle of the jnotlinrax, and the apical end of the 

 elvtra. In the form whii-h was dtice knnw u as ('. tenninalt, Init which 

 is now regardeil to lie a variety of ('. rrli'-iilatiun, the anterior two-thirds 

 of the elytra are yellow, while in (jtlier sjieciniens there is a patch of 

 black near the base of each elylnai. These insects vary from (1.40 to 

 0.75 of an ini'h in length. Their hirv;e are clay-yellow, Jirettily marked 

 witli black, and are found under logs and stones, where they eat other insect larvie. 



The Elateiud-E, includinir with them the Eucxe.miu.e and Ceukionid-E, which 

 are often regarded as dist inct f.innlies, <'om]irise consideralilv nmre than three thou- 

 sand species of desci-ibed coleojitera, which are ijuite distinctly separated by a few 

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

 Ib.irn's work, til which reference has been so often made: The antenna' are usually 

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

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

 is not elongate ; the hind coxa- are (■(jutiguous, and silicate for the reception of the 

 thighs; tiie front coxa' glolmsi', and contained entirely within the prosternum ; the 

 ]irothorax loosely articitlated to the mesuthorax, and the prosternum prolonged behind. 

 The greater jiart of the Elaterida- are |)opularly kudwn in America as snapjiing- 

 beetles and spring-l)eetles, and in Englaml as click-beetles and skipjacks, because of 

 tlieir jiower <jf jumping up into the air when ]ilaced upon the liack. Dr. Le Conte 

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

 spine to the anterior part of the mesosternal cavity, then suddenly rel.'ixing tile muscles 

 so that the sjiine descends violently into the i-ax itv, the force given bv this sudilen 

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

 elasticity the liody is jiropelled upward." Without the aid of this mechanism, these 

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

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

 the ground, with legs retracted and feigning death, u|)on the slightest disturbance. 

 If a beetle fails to regain his jiroper jicisition by the first jump, the springs are repeated 

 until success residts, each spring, esjiecially if upnu a liai'd surface, is accomjianied by 

 a distinctly amlible click. 



The habits of the Elaterida' are (juite diverse, many sit upon leaves of jilants and 

 upon grass, others are .'ibundant under bark, and many species live concealed beneath 

 stones. 'I'he lar\a' U'-ually live in decaying wood; some of them, however, do not 

 confine their attacks to dead vcgetal:ile matter, but are known as seriously injurious to 

 li\ ing Jilants and to cultivateil crops ; a few of these larva' are carnivorous, the larva- of 

 Drasterais aiiiii/n7i.-<. in the I'nited States, beiie^- kimwn to <levour locusts' eggs. !Many 

 elaterid larva-, liecause of their cylindrical lV)rm and very firm, smooth, chitinous 

 exterior, are knowir as wire-worms. The larva^ have si.x legs, no ocelli, and their 

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

 potatoes and ealiliage roots by riddling them with their bin-i'ows. Some of these larvte 



