264 COLEOPTERA CHAP. 



colours, are diurnal in habits, and some of them run 

 with extreme velocity in places so bare and desert that the 

 means of existence of the Insects is a mystery. Most of the 

 Tenebrionidae, however, shun the light. The food is usually 

 vegetable matter, and it is apparently preferred in a very dry 

 state. Mr. Gahan has recently recorded that in Praogena 

 the under surface of the head has the gular region striate for 

 stridulating purposes. This is the only instance known of a 

 voice -organ in this situation, and moreover is the only case 

 in all the Tenebrionidae in which any sound-producing organ 

 has been discovered. The larvae exhibit but little variety, they 

 are elongate and cylindrical, with harder integument than is usual 

 in Coleopterous larvae ; they have six thoracic legs, and at the 

 under side of the posterior extremity the anus serves as a very 

 short pseudopod. The resemblance of these larvae to those of 

 Elateridae is considerable : but though the body is terminated by 

 one or two small processes, these never attain the complexity of 

 the terminal segment of Elateridae. The common meal-worm 

 i.e. the larva of Tenebrio molitor is a very characteristic example 

 of the group. The pupae are remarkable on account of peculiar 

 projections, of varied and irregular form, that exist on the sides 

 of the abdominal segments. Britain is very poor in these Insects ; 

 our list of them scarcely attains the number of thirty species. 



Fam. 63. Cistelidae. Claws comb-like. The very obscure 

 beetles forming this family are only separated from Tenebrionidae 

 on account of their pectinate claws. About 500 species of Cis- 

 telidae are recorded ; the early instars, so far as known, do not 

 differ from those of Tenebrionidae ; the larvae are believed to live 

 on dead wood. 



Fam. 64. Lagriidae. Anterior coxal cavities dosed, tips of 

 the front coxae free, claws smooth, penultimate joint of the tarti 

 broader, j>t>l>rxecnt beneath. This family has very little to dis- 

 tinguish it from Tenebrionidae, and the group Heterotarsini 

 appears to connect the two. It is a small family of about 200 

 species, widely distributed, and represented in Britain by one 

 species, Lai/fia hirta. The early instars are similar to those of 

 the Tenebrionidae, except that the larva is less retiring in its 

 habits and wanders about on foliage: it is of broader form than 

 that of most of the Tenebrionidae. The pupa has long projections 

 at the sides of the abdominal segments. 



