108 CLAVICOUNIA. [Trichopterygina. 



tion consisting of six or seven segments ; the legs are moderate, short in 

 some genera, with 3-jointed tarsi, the last joint terminating in two 

 equal claws. 



The Trichopterygidae are known already to comprise a considerable 

 number of genera (twenty-one are enumerated by Mr. Matthews, and 

 others have been described by him), and a large number of species; as, 

 however, fresh representatives are perpetually being found in every 

 quarter of the world in which they are looked for, it is most probable 

 that the genus is one of the most extensive and most widely distributed 

 of all the Coleoptera. 



The larvae of Trichopteryx, Pleryx, and Ptinella (the only genera known in that 

 state) are stated by Mr. Matthews to resemble each other so closely that one de- 

 8cript<on is sufficient to characterize all of them ; in his Monograph the larva of 

 Plinella is described on page 50, and figured PI. I. figs. a. b. ; it is slender and elon- 

 gate, almost moniliform, transparent and crystalline in appearance ; the head is large, 

 subtriangular, with prominent eyes; antenna} short, last jo; ut furnished with long 

 setaj ; the segments are of about equal breadth, the abdominal ones being all fur- 

 nished with a strong short seta on each side ; last segment large, bearing two cerci 

 terminated by long setae : legs short, tarsi formed apparently of one joint terminated 

 by a single claw. 



The family may be divided naturally into the two following tribes : 



I. Elytra truncate TBICHOPTEBYGINA. 



II. Elytra not truncate PTILIINA. 



TRICHOPTERYGINA. 



This tribe contains eight European genera, all of which, except 

 Astatopteryx are represented in Britain ; some authors still consider 

 Bceocrara, Thorns., formed to include T. variolosa, to be distinct, but 

 it only differs from Trichopteryx in sculpture, and cannot with good 

 reason be separated on that point alone. 



In the following tables and descriptions I am much indebted to Mr. 

 Matthews for his kind help, extending over a period of several years, 

 during which I have taken a considerable number of the rarer species 

 belonging to the family ; at the same time it must be admitted that no 

 very satisfactory tables can be drawn up, and that in some of the 

 genera, more especially in Trichopteryx, it is extremely difficult to 

 determine the more closely allied species from descriptions, and that 

 long practice and comparison with authentic types is the only method 

 by which anything like accuracy can be arrived at in this most difficult 

 group ; the difficulties are increased by the fact that the colours, espe- 

 cially of the antennae, appear to alter to a greater or -less extent after 

 death, unless very great care is taken with regard to preserving and 

 setting the insects. 



J. Thorax not contracted or constricted behind, 

 i. Abdomen with seven free ventral segments. 



