COLEOPTERA CHAP. 



ii. The MELOLONTHIDES are probably almost as numerous as the 

 Coprides, some 4000 species being already known. The larvae 

 are believed to feed chiefly on roots. Melolontha n//i/it,-is, the 

 common cockchafer, is very abundant in some parts of Europe, 

 and owing to this and to the great damage it causes, has attracted 

 much attention. The memoir by Straus-Durckheim * on its 

 :i i KI i M i v is one of the classical works of Entomology. This In- 

 sect is so injurious in some parts of France that money is paid 

 by the local authorities for its destruction. M. Eeiset informs 

 us that under this arrangement 867,173,000 perfect cockchafers, 

 and 647,000,000 larvae were destroyed in the Seine-inferieure 

 in the four years from the middle of 1866 to 1870. Unlike 

 the Coprides, the larval life in Melolonthides is prolonged, and 

 that of the imago is of brief duration. In Central Europe the 

 life-cycle of the individual in M. ridyaris occupies three years, 

 though in dry periods it may be extended to four years. In 

 Scandinavia the time occupied by the development appears to be 

 usually five years. The fertile female enters the ground and 

 deposits, its eggs in two or three successive batches of about 

 fifteen each. The eggs swell as the development of the embryo 

 progresses ; the larva emerges about five weeks after the eggs 

 have been deposited, and is of relatively large size, "When 

 young the larvae can straighten themselves out and crawl, but 

 when older they lose this power, and when above ground rest 

 helplessly on their sides. In the winter they descend deeply 

 into the earth to protect themselves from frost. The pupa 

 state lasts only a few days, but after the final transformation the 

 perfect Insect may remain motionless for as much as eight 

 months underground before commencing its active life in the air. 2 

 In the perfect state the Insect is sometimes injurious from the 

 large quantity of foliage it destroys. Schiodte 3 considered that 

 these larvae (and those of numerous other Scarabaeidae) stridu- 

 late by rubbing certain projections on the stipes of the maxilla 

 against the under-surface of the mandible. These surfaces appear, 

 however, but little adapted for the purpose of producing sound. 



iii. The EUTELIDES number about 1500 species ; there are many 



1 Considerations generates sur Tanatomie comparee dcs animaux articules, etc., 

 Paris 1828, 4to. xix. and 435 pp., and Atlas often (xx.) plates, and 36 pp. 

 - Raspail, Mem. soc. zool. France, vi. 1893, pp. 202-213. 

 3 Ann. soc. cut. France, (v.) iv. 1874, p. 39. 



