ArpUS.] ADEPIIAGA. 125 



eyes very small sunk into the hcatl, black, mandibles large and strong ; 

 thorax cordiform with anterior margin straight, sides obliquely con- 

 tracted towards base, posterior angles sharp, rather minute ; elytra 

 parallel-sided, with irregular traces of strife and punctuation, usually 

 with two or three or more distinct large pores or impressions on each ; legs 

 testaceous. L. 2 mm. 



Lociil, Init occasioiKilly ])lontiful wliorc it oconrs ; Lnccombe Cliinp, and Vcntnor, Tsle 

 of VV'itjlit ; Woyiiiouth ; VVateriiioutli (North Devon); I )oiiif()i-(l (Somerset) ; mouths 

 of tlic Tamar and Yeanie and other h)ealities in the south-west ; Northninl)erhind and 

 Durham district, 15er\vi('k-u])(jii-'r\v('ed, &c. ; .Seotlaud, h)cal, Tweed, Forlli, and Clyde 

 districts, iu the Isles of liute and Arran, &c. ; Irehmd, near Duhhu, and Slraiigford 

 Lough. 



A. Robinii, Laboulb. Very like the preceding, but differs in the 

 following jiarliculars : the thorax has the iJosterior angles considerably 

 blunter, and the sides less sinuate before base, the dorsal furrow Itcing 

 much less apparent ; the elytra are less parallel-sided and are dilated 

 behind middle and shorter, and the entire upper surface is smoother and 

 shows less trace of sculpture. L. 2 mm. 



Karer than the jirocediug ; Weymoutli ; Ventnor ; Plymouth ; Xorthumberiaud 

 and Durham district. Scotland, Tweed and Forth districts. 



TXLSCHUS, Clairville. 



The genus Trorhvs proper comprises about one hundred and thirty 

 speci(;s, which vary considerably in size and general appearance ; they are 

 chieHy found in Europe, Xorth America, and the Atlantic islands 

 (]\ladeira, &c.) ; a very small proportion come from the southern hemi- 

 sphere : some authors include under Tri'cltiis the peculiar genera Anoph- 

 thahnus and A2>httnops, which are distingiiished b}' having no eyes ; 

 these are found in the caves of the Pyrenees and the Alps and in North 

 America (especially Kentucky), and number about fifty species ; two 

 species of Aplatnops, as Bedel points out (1. c. p. 40), have the anterit)r 

 tarsi simple in both sexes as is the case in some species of Tarliijs, and 

 one species of Trechus {T. oclrreafu.s) from the Ausliian Alps has the 

 posterior femora dilated and denticulate in the male. 



Our species may be subdivided as fullows : — 



I. Elyti'a finely pubescent. 



i. Elytra reddish, with a broad black liand 



behind middle ; striic plainly jiuncUired T. Discrs, F. 



ii. Elytra reddish yellow, with u very ob- 

 scure black spot (often absent) towards 

 npex of each ; stri:c almost impnuctate T. MICR03, Ilerlsl. 



II. Elytra not pubescent. 



i. Posterior angles of thorax sometimes 

 sharp, sometimes very blunt, but always 

 traceable. 



1. Elytra with parallel sides; antenna"' 



very long T. lONOICOBNiS, Sfiirm. 



2. Elytra with sides rounded ; antenmu 

 nioilerate. 



