454 COLEOPTERA. 



sus Beauv. Fig. 407), is described by Chapuis and Candeze as 

 coming from New Orleans. 



Melolontha and its allies come next in tlie scries. The}^ feed 

 exclusivel}^ on living plants. The genus Acratus was estab- 

 lished by Dr. Horn for A. Jlavipennis Horn (Fig. 

 408 ; a, antenna ; &, maxilla ; c, mentum ; cZ, mandi- 

 ble ; e, anterior leg and tarsal claw) found in Ari- 

 zona. The genus BichelonycJia is distinguished by 

 the front margin of the thorax being narrow and 

 membranous, with equal claws, cleft at the tip. Bi- 

 chelonycJia elongatula Schonii. is a long green beetle, with long 

 legs, and of a metallic green color ; it is found in June on the 



leaves of the birch. 



Macrodadylus sub- 

 sjnnosus Fabricius, the 

 well known Rose-bug 

 or Rose- chafer, is 

 brown, covered with 

 ochi-eous scales ; the 

 408. legs, tarsi and claws 



are very long and slender. It overruns garden plants, especi- 

 ally injuring the rose leaves. Dr. Harris has observed the 

 transformations of this insect. The nearly globular whitish 

 eggs, about thirty in number, are deposited b}^ the female 

 from one to four inches beneath the surface of the soil, and are 

 hatched in about twenty days. The whitish 

 larva becomes fully grown in the autumn, and 

 is then three-quarters of an inch long and an 

 eighth of an inch wide. In October it descends 

 below the reach of frost, and in the next 

 May is transformed to a pupa in an oval 

 earthen cell. The pupa is yellowish Avhite, 

 somewhat of the form of the beetle, with short wings ; its 

 antennae and legs folded on its breast, with its white body 

 surrounded by a thin fihn. The beetles may be often seen in 

 clusters on low bushes in partially cleared fields having just 

 appeared from their cocoons. Dr. Horn has described the 

 genus Plectrodes for a Californian species, P. pubescens Horn 

 (Fig. 409 ; a, maxilla and palpus; b, tarsal claw). The well 



