144 



INSECTS. 



Bwprestidce, and differ also in having the posterior angles of the pronotum sharply 



produced behind, and the prosternal process laterally compressed and slightly 



curved, with its point resting in a deep cavity in the mesosternum. Their antennae 



— consisting of eleven, or rarely twelve, joints 

 — are usually serrate, though in many cases, 

 especially in the males, they are either pectinate 

 or flabellate. These beetles owe their name of 

 skip-jacks to the power they have, when fallen 

 on the back, of springing into the air and 

 alighting on their legs again. The larvae of 

 some species eat into soft succulent roots and 

 tubers, and in this way prove destructive to 

 many of our cultivated plants. These pests are 

 well-known to farmers under the name of wire- 

 worms. The larva of Agriotes lineatus is one 

 of the worst, being destructive not only in the 

 fields but also in the kitchen-garden. It is of 

 a pale yellowish brown colour, differing little 

 in general appearance from the larvae of other 

 species, and lives for probably four or five 

 years, passing then into a pupa, which remains 

 concealed in the ground for a few weeks before 

 changing into the perfect insect. Amongst the 

 exotic members of this family, the most remark- 

 able are the fire-flies, found in the West Indies 

 and America. There are several species of 

 these beetles, all belonging to the genus 

 Pyrophorus, one of which, P. noctilucus, is 



illustrated on p. 146. They have a dark brown or reddish brown colour, obscured 



by a covering of short grey hairs, and may be easily recognised by the 



two slightly raised yellow spots placed near the 



hind angles of the prothorax. In the living 



insect these spots glow with a rich yellowish green 



light. A stronger but more diffused light of 



a reddish colour is given off from the abdomen 



when the beetles are flying. 



The remaining families of the section Penta- 



mera are included in the tribe Malacodermata. 



The beetles of this tribe are distinguished by 



having the elytra less solid and compact, and the 



body in general softer and more flexible than is 



usual in other groups. The Lycidce are deserving of notice, inasmuch as they 



form one of those groups of insects which are most frequently mimicked by species 



of other families. They have a characteristic appearance, owing to the small 



size of the head and prothorax, as compared with the greatly expanded elytra. 



To their unusual shapes these beetles generally add a conspicuous coloration; 



SUMMER-CHAFER (uat. size). 



rhinoceros-beetle, male (cat. size). 



