Ptinella.] CLAVICORNIA. 113 



Under bark of various dend trees, of ten in company with P. aptera, locally com- 

 mon ; Sherwood Forest ; Sutton near Birmingham ; Solihull ; Salfbrd Priors ; 

 Cannock Chase ; Windsor; Wickeu Fen. 



P. tenella, Er, (1 microscopica, Waltl.) Elongate, very narrow, 

 pale yellow, clothed with short pale hairs ; head large, elongate in front, 

 eyes (at all events in the female) very large, antennae rather long, pale 

 yellow ; thorax very short, much shorter than head, with sides rounded 

 in front, and strongly constricted behind, posterior angles prominent, 

 very acute, extremely finely tuberculate ; elytra long and narrow, much 

 longer than head and thorax, with sides scarcely rounded, very h'nely 

 asperate in remote transverse rows, apices strongly rounded, with a lon- 

 gitudinal band of darker colour in the female : legs rather long, pale 

 yellow. L. f mm. 



Very rare ; one example has heen taken by Mrs. Matthews under bark of dead oak 

 in Sherwood Forest ; it is very rare on the Continent. 



The species may be known by its very short thorax, which is strongly 

 constricted behind, long elytra, and firie sculpture. 



TRICHOFTERYX, Kirby. 



This genus contains a very large number of species ; seventy- four are 

 enumerated by Mr. Matthews in his monograph, but a considerable number 

 have since been described from Central America and other parts of the 

 world, and the genus is so widely distributed that it is probable that only a 

 small fraction of the existing species are at present known, as very few col- 

 lectors trouble themselves to look for them ; they are distinguished by not 

 having the thorax constricted behind and by the fact that the abdomen 

 has six free ventral segments ; they are very rapid in their movements and 

 run with a swift jerky motion very different from that of Ptenidium and 

 Pt ilium; there are thirty-nine British species at present known, which in 

 many instances are exceedingly closely allied, and require the greatest care 

 in their determination ; they may be roughly divided as follows, but, as 

 above stated, no really satisfactory table can be formed ; the colour, for 

 instance, is in many cases a very important point, but immature 

 specimens of the black species are sometimes reddish or brownish ; 

 Mr. Matthews and I once found a large number of a brownish-looking 

 Trichopteryx in faggots in Sherwood Forest, which we thought at first 

 must be a good species, but they turned out to be very slightly 

 immature T. fascicularis ; the only way to work the genus is first to 

 separate those that seem at all differently formed by a simple Codding- 

 ton or Browning's platyscopic lens, and then to compare them carefully 

 with authentic specimens of the species to which they seem to belong 

 under a compound microscope, with a rotating stage, as the asperate 

 sculpture presents a very different appearance in different lights. 



The species are chiefly found in hot-beds, haystack refuse, dead leaves, 



VOL. III. I 



