186 SERRICORNIA. [AnobiidoB. 



A considerable number of genera and species are contained in the 

 family, which is by many authors included as a tribe under the 

 Ptinidae ; these are widely distributed over the surface of the world, but 

 appear to be chiefly characteristic of temperate and colder climates ; 

 five of the eight European genera are represented in Britain; the larvae 

 differ but little from those of the Ptinidae, and do not require any 

 separate description. Professor Westwood observes (Classification, i. 

 271) that when full fed they construct a cocoon of soft silky matter, 

 mixed with the substances upon which they have been feeding, within 

 which they are transformed to pupae, and that it would appear that the 

 larva has the instinct to continue the boring of its burrow until it has 

 nearly reached the surface, so that a slight barrier only remains, which 

 the perfect insect can pierce without difficxilty. 



The family may be divided, for convenience sake, into the following 

 three tribes : 



I. Antennae not serrate or pectinate, with the last three joints 

 longer and usually broader than the preceding ; first ventral 

 segment not excavated for the reception of the hind legs (in 



our species) * ANOBIINA. 



II. Antenna? serrate or pectinate, rarely flabellate, with the last 

 joints, as a rule, not longer than the rest ; first ventral seg- 

 ment not excavated for the reception of the legs XYLETININA. 



III. Antennae with the three last joints serrate, much enlarged ; 

 first ventral segment deeply excavated, on each side, for the 



reception of the hind legs DORCATOMINA. 



ANOBIINA. 



In this tribe the head is much deflexed, and received when at rest on 

 the under surface of the thorax, which is excavated beneath to receive 

 it, except in Di-yophilus; this latter genus might perhaps, with 

 advantage, be formed into a separate tribe, as it also differs in the 

 formation of the antennae, which have the last joints more slender in the 

 male, and are more contiguous at base ; the antennae, in the tribe, are, as 

 Dr. Horn observes, usually received into a more or less distinct 

 excavation between the front and middle coxae, which is sometimes pro- 

 longed into the metasternum, but the head is never excavated beneath 

 for their reception; the fifth joint of the tarsi is very often dilated and 

 membranous beneath. 



The species belonging to this tribe are mostly found in old wood, and 

 several frequent old houses ; during the season of pairing they have a 

 habit of striking their jaws upon the wood on which they are standing 

 as a signal to their mates, who reply in the same manner ; this produces 

 a ticking noise, which is scarcely audible in the day when various other 



The first ventral segment is excavated in Theca and Eupactus ; the former 

 genus, however, appears to be now referred by some authors to the Dorcatoimna. 



