180 



INTRODUCTION. 



off at will. The object of this provision in certain of the Phyto- 

 phaga is not quite clear, but it is possible that it may serve 

 as a means of protection and defence. According to Sharp and 



Fig. 82. — Sagra femorata (natural size). 



other authors many of the Crioceein^ have the power of stridu- 

 lating, the organ bei.ug situated at the base of the last dorsal 

 abdominal segment, and consisting of five raised lines which are 

 rubbed by the apex of the elytra. 



2. Cyclica. — These include the mass of the Chrysomelid^: 

 (Lamprosoma, Eumolpus, Chrysomela, Nodostoma, etc.). Occasion- 

 ally the larvae are injurious to vegetation. The well known 

 Colorado potato-beetle (Leptinotarsa decem-lineata) belongs to this 

 group, as also does the mustard-beetle (PJicedon), etc. The 

 species of this and the succeeding group are in many cases the 

 most permanently brilliant of the whole family, but are surpassed 

 by many of the Cryptostomes, while the latter are living or in 

 quite a fresh state. 



3. Camptosomes. — This group includes the well-known genera 

 Cryptocephalus, Clytra, Chlamys, and Gynandrophthalma, the 

 remarkable Longicorn-like genus Temnaspis, before referred to, 

 and several others of considerable interest. The larvae of a 

 number of the species live in portable cases ; those of Crypto - 

 eephalus (Weise, Naturg. Ids. Deutsch. vi, p. 139) remain, with 

 the abdomen curved against the breast, in a cylindrical bag, 

 which is narrowed in front and from which they can only emerge 

 as far as the first abdominal segment ; this case is carried in an 

 oblique, almost upright, position, the larva progressing with a 

 jerky motion. The pupae are attached to dry leaves and stems of 

 grass. 



