512 INVERTEBRATE MORPHOLOGY. 



the imago, very different in appearance from the pupa. The 

 metamorphosis here approaches the complete type. 



9. Order Coleoptera. 



The order Coleoptera includes the Beetles and is richer 

 in species than any other order of animals. The members of 

 the group are characterized by the anterior wings being con- 

 verted into hard chitinous plates, the elytra, which cover in 

 and protect the posterior membranous wings and the abdo- 

 den, being short only in a few forms, such as the Buryiug- 

 beetles (Necrophorus), in which the tip of the abdomen remains 

 exposed, and the Staphylinidse, or Rove-beetles, and Meloe, in 

 which they cover only the more anterior portions of the ab- 

 domen, the posterior wings in the last-named form being 

 wanting, as they may also be in some of the Weevils. Occa- 

 sionally, as in the Fireflies (Lampyris), the elytra are but 

 slightly thickened, and in some forms they may be completely 

 fused together. 



The antennae vary greatly in shape, being usually filiform 

 and sometimes very long, as in the Boring-beetles (Monoham- 



FIG. 239. Cotalpa lanigera AND ITS LARVA (a) (from PACKARD). 



mus, Clytus, Saperda, etc.), though occasionally, as in the 

 Lamellicorn beetles (Melolontlia -the June Bugs and Cotalpa, 

 Fig. 239), the terminal joints are flattened and folded together 

 like the leaves of a book. The mouth-parts (Fig. 225) are in 

 all cases adapted for biting, and the legs for locomotion. In 

 the Lady-bugs (Coccinella) the tarsus consists of but four 

 joints, one of which is rudimentary, while in the Weevils 

 (Curculionidne), in which the anterior part of the head is pro- 



