366 



NATURAL HISTORY OF ARTHROPODS. 



Fig. 423. — Chalco- 

 phora virginiensis. 



Fig. 424. — Gyascutus 

 planicosta. 



elytra, the species of Chrysobotfirys, but are generally larger and have a distinct sixth 

 ventral segment. C. liberta, from the eastern United States, is light copper-bronze in 

 color, the elevated portions of the surface being polished while the 

 depressed parts are dull. It feeds, as larva, in pine woods, as does 

 also C. virginiensis, which is generally a little darker colored and 

 somewhat larger; the former species is from 0.75 to 1.10 inches long. 

 The larvffi of both sfiecies inhabit pine wood. Gyascutus and Psilop- 

 tera are genera only represented by a few large species, from western 

 North America, of which the earlier stages are unknown ; they are 

 separated from Chalcophora by their having the mentum rounded in 

 front ; they are distinguished from one another by the first joint of 

 the posterior tarsi being elongated in Gyasctitus, and not elon- 

 gated in Psiloptera. Near these genera in classification are the 

 giant South American species of Euchroma, of which E. gigantea 

 has been already mentioned, and the brilliant oriental and African 

 species of Chrysochroa, the latter generic name being compounded 

 from two Greek words meaning "gold " and " skin." Chrysochroa 

 ocellata, a large species from the East Indies, is beautiful shining 

 green, with elytra marked with golden and yellow spots, and three- 

 toothed at the apex. Sternocera, another Asiatic and African 

 genus, contains large and brilliant species, in which the sternum 

 is prolonged forward and downward as a horn. Sternocera chrysis, 



a large species with chestnut-brown elytra, lays elliptical white eggs 

 that are 0.36 of an inch long and 0.24 of an inch in shorter diameter, 

 and from which the larvae at hatching are about 0.45 of an inch 

 long. 



The described species of Scaeab^id^ number over seven 

 thousand. They are readily separated from all other Coleoptera 

 by the form of their antennfe, in which the outer joints — usually 

 three, sometimes as many as seven in number — are flattened 

 lamellfe capable of close approximation to foi-ra a club, and by 

 their fossorial legs. The antennas, which are inserted beneath 

 the sides of the front, have from seven to eleven joints; the 

 first joint is always elongated, and the second thicker than the 

 third. On account of the form of their antennae, beetles of this family are often called 

 lamellicorns. There are no very minute species of Scarabssidfe ; the family, on the 

 other hand, contains some extremely large insects, the veritable elephants among 

 Coleoptera. The lamellicorns, of course, reach their greatest development, both as to 

 number and size of species, in the tropics, but species of considerable size are not 

 wanting in the temperate zone. These beetles attract the attention of people not 

 generally interested in natural history, not only on account of their large size, but 

 also because of their curious habits, sometimes useful to man, as are those of the 

 dung-beetles, one of which {Aieuchus sacer) was long recognized as sacred by the 

 Egyptians. 



Quite a number of genera are wingless, although the greater part can fly. A large 

 number produce sounds, either by stridulation, by the motions of the wings, or in some 

 cases by the rapid passage of air in or out of the stigmata. Sonifaotion is not confined 

 to imagos, for many lamellicorn larvas stridulate by rubbing the maxillae against the 



Fig. 425. — Chrysochroa 

 ocellata. 



