424 



ARFHROrOPA 



^vinJ;s. The anterior pair, separated at the base by a seulellum. are hard 

 clw'yj not luted for lliuht, and from these eomes the name Coleoplera, 

 sheath wings. Ihuier the elytra are proieeted llie deUeaie nuieh fohled 

 liinder wings, the organs of ihght. Sinee the seeond and llrirdlhoraeic 

 riniis and those of \hc abdomen are eovered by tlie elytra, these are so;t 

 above. Kxternallv the relations of the elytra eause a regional division 

 peeuliar to the lieetles ^lig. 471"): head, prothorax, aird a third di\isioa 

 composed of nieso- and metathorax plus abdomen eovered by the el\-lra. 



The numerous speeies of beetles — over 100.000 di-scribod — are dixided into 

 normal forms and Rhynehophora, the normal I'.irms being siibdi\ided uiion 

 charaeters derived from the tarsi as follows: 



Sub Order I. PEXT.VMERA. Tarsus live-jointed, the last club-shaped 

 and bearim.; the claws; the other four are shma and somewhat heart-shaped 

 (,hi;. 47^, d). This largest sub order coiuains the tiger beetles (Cicixdelip.vO, 

 the predaccous C.Ai^AiurT.i: i^lig. 471); water lieeiles, HYDEOnitl.ili.K and 

 Dytiscid-E; L.vmellicorxlv or Sc.\R.ABEiD.i:, represented by the 'June bugs,' 

 ^^cIoloIllIla*; fire liies, L.^iirYRiD.E; rove beetles, Sr.\rHVLtxiD.K, etc. Sub 

 Order II. HETEROMERA. First and second legs pentam- 

 ennis, third apparendv four-jointed; few species; 'oil bottles' 

 ^MiLOtr.i;) and the blister beetles, C.\xtei:\riP-E, both con- 

 taining a jieculiar substance, cantharidin, which renders the 

 'S]>anish flies,' an important ingredient of blistering })lasters. 



TrXKlU^IOXID.E. 



Sub Order III. TETRA^^IERA (Cryptopentamera). 

 Tarsi with the penult joint rudimentary, gi\"ing the impres- 

 sion of four joints i,lig. 472, b). The families numerous in 

 species, are injurious to vegetation. The larva' of Cer.am- 

 BVCID.E bore in wood. The CHRVSOKELin.r: (Colorado 

 4--. — jR,7- potato beetle, Poryphorj''') feed on lea\es. Sitb Oixler 1\'. 

 !a)ii!iiis iiLiiirusr' TRIMER.V; tarsi with penult and antipenult ioinls rudi- 

 hazel-nut \vee\il. menlarv, so that thev appear three-iointed. CoeciXELLID.E, 

 lady birils, wliose lar\\e, because of feeding on plant lice, 

 etc., are of \-alue to man. Sub Carder W RHA'NCIUTMIOR.V, snout beetles; 

 heatl produced into a long snout with mouth parts at apex. Here belong 

 weevils, which damage grain, nuts, limber, etc. Ciiri.iil:o/' Coiu'trachcltis* 

 Calaitilrj,''' Boljuiiuis'-' (fig. 47J). 



Order VII. Hymenoptera. 



Tire Hymenoptera, of which bees, wasps, aird ants arc well-known 

 icpresentati\es, ha\e biting mairdibles, while the other mouth parts are 

 elongate and in a miiunaty of the group cotiverled into a sucking orgaii 

 (p. 4o(>). Since mouth ptirls vaiw, (he wings atrd bodv segmentation 

 ha\'e gretit \-alue iu defming the order. The wings are membranous and 

 are supported by few ner\ures (lig. 474), and in llight thev act as one 

 pair, siiree the two are usually connected by hooked bristles on the hind 

 wing, wliich eiygage in a grooxe oi: the hinder tnargin of the front wing. 

 The fore wings are the larger and, correspondingly, tlie mesothorax 



