COLEOPTERA. 475 
dark greenish brown, yellowish on the sides. The elytra of the 
male are smooth ; those of the female are fluted. The front leg of 
the male is provided with suckers. The larva is brown; the pupa 
of a dirty white. 
The Dytiscus marginalis sometimes attacks Hydrophilus piceus. 
It pierces it between the head and the thorax, that is, in the 
weak point of its cuirass, and devours it, in spite of it being the 
stronger. The largest of the Dytisci, the Dytiscus latissimus 
(Fig. 475), is almost confined to the north of Europe. The Cydis- 
ters abound especially in warm countries. The Cydster Reselii 
(Fig. 476), a European species, has the reputation of having been 
taken in England. This group contains also a great number of 
insects more or less resembling the preceding, in their conforma- 
tion and habits. We will confine ourselves to representing a few 
by figures :-— 

Fig 477.—Acilius sulcatus (male). Fig. 473.—Acilius sulcatus (female). 

Big 479. Fig. 480. Fig. 481. 
Acilius fasciatus (male). Acilius fasciatus (female). Noterus crassicornis. 
