Tachtjporus.] staphylinid^. 193 



TACKVPORUS, Gravenhorst. 



The species belonging to this genus are easily distinguished from the 

 preceding by their much brighter appearance, which is due to the absence 

 of pubescence on the head and thorax, and its scantiness on the hinder 

 parts of the body ; the genus comprises some fifty species, which are con- 

 fined to the northern and temperate portions of tlie Old and New Worlds, 

 and are within their range evenly distributed ; they are chiefly found in 

 moss ; one or two species are exceedingly common, and from their bright 

 colouring are well known to ordinary observers as well as to entomolo- 

 gists ; in fact it is hardly possible to gather a handful of moss without 

 finding in it either T. hijimoruni or T. chrysomelinus ; the sexual 

 characters, although somewhat striking, are very much alike in the several 

 species, and need not be separately described : in tlie male tlie seventh 

 dorsal segment of hind body is entire, and somewhat rounded at apex, 

 the seventh ventral segment is strongly emarginate, disclosing the seg- 

 ment of armature, and the anterior tarsi are plainly dilated ; in the female 

 the seventh dorsal segment is furnished with four narrow sharp lobes of 

 about equal length, the outer pair differing slightly in shape, and the 

 seventh ventral segment is prolonged, rounded, and ciliate, concealing tlie 

 segment of armature ; the anterior tarsi in the latter sex are feebly 

 dilated ; the external structural differences of the species throughout 

 the genus are very slight, and it will be noticed that the distinctions 

 rest in great measure on size and colour variations ; as a natural con- 

 sequence there are considerable difli"erences of opinion regarding the 

 specific value of some of the species that have been described. 



The larva of TacJiyporus chrysomelinus very much resembles in structure that of 

 Tachinus rufipes, and is chiefly distinguished by its stouter antennae, and the absence of 

 warty prominences at the apex of the anal appendage ; it is about quarter the size of 

 the hist-mentioned larva, and is pale, with the head and prothorax yellow, and all the 

 setse pale ; the scuta of the rest of the segments and the first joint of the cerci are 

 somewhat fuscous. 



I. Head and thorax reddish testaceous. 



i. Elytra testaceous, with basal half black ; hind body 



testaceous with sixth and seventh segments black . T. obtustjs, L. 



ii. Eljtra testaceous, with scutellary region only darker ; 

 hind body black (reddish in immature specimens), 

 with sixth seginent testaceous T. FOEMOSirs, Matlh. 



II. Head black or pitchy black. 

 i. Thorax entirely testaceous. 



1. Antennae plainly, although not strongly, thickened 



towards apex ; elytra reddish testaceous or yel- 

 lowish, not darker at sides. 



A. Thorax and elytra testaceous red ; size larger ; 



antennae testaceous with base lighter than the 



rest T. SOLUTUS, Er. 



B. Thorax and elytra straw-coloured ; size smaller ; 



antenna; dusky towards apex T. PALLIDAS, Sharp. 



2. Antennae not thickened ; elytra reddish testaceous 



or reddish brown, darker at least at sides. 

 VOL. II. O 



