COLEOPTERA. 



153 



strongly transverse, and their sockets widely open behind, the sides of the prothorax 

 are sharply edged, the palpi are never pointed at the end, and the front tibiae are 

 without a groove underneath. This subfamily is the least numerous in species, 

 though many of these are distinguished for their great size. Titanus giganteus, a 

 Brazilian species, sometimes measures over half a foot long, and is the largest of all 

 known beetles, while the sawyer-beetle (Macrodontia cervicornis) and other species 

 occurring in Tropical America, are not much smaller. Most of the Prionince are 

 found in the warmer parts of the world. They are represented in Europe by 

 Prionus coriarius, Ergates faber, and a few other forms. P. coriarius is the only 

 species which occurs in England, and is not very common, being met with chiefly 

 in oak-woods, where the larvae live in the rotten trunks of trees. The Ceram- 



Prionus coriarius, female ; and Ergates faber, male (nat. size). 



bycince are widely distributed and include a very large number of species. They 

 are as a rule narrower than the Prionince, and without sharp lateral edges to the 

 prothorax, while the sockets of their front-legs are seldom strongly transverse and 

 are often rounded and completely closed behind. Most of the species have a 

 stridulating area on the mesonotum, and by this means are enabled to produce 

 sounds. This subfamily includes a number of very remarkable mimetic forms, 

 some with broadly expanded elytra, and black and tawny colours resembling 

 Lycidce, others with the elytra greatly reduced in size, and the shape of the body 

 modified in imitation of various Hymenoptera. The metallic-coloured beetles of 

 the group Callichromides, most of which are found in tropical countries, exhale a 

 scent resembling otto of roses. In England this group is represented by the musk- 

 beetle (Aromia moschata), figured on p. 154, a handsome insect of a golden-green 

 or bronzy colour, which is met with on willow-trees. Amongst the European species of 

 Cerambycince, the groups Lepturides, Molorchides, and Clytides are best represented. 

 Some of the Lepturides, such as Strangalia and Toxotus are flower-frequenting 



