The Male Genital Armature of the Dermaptera. 443 



But the metaparameres are very remarkable ; they are short, 

 the inner margin straight, and outer margin rounded ; the apical 

 part of the inner margin is strongly dentate ; four sharp teeth, one 

 being bifid, are discernible. Running backwards from the apical 

 tooth is a curved keel which terminates in a strong recurved 

 crested tooth or acute lobe, directed posteriorly ; from the base of 

 this crested tooth there runs a branch of the keel, across the 

 segment, connecting up with a slight longitudinal keel, which does 

 not reach the edge of the segment. The appearance of this com- 

 plex armature varies with the aspect, and though I have examined 

 two specimens, I am unable to say if both pairs are exactly alike 

 in detail ; probably not. At least, in the figured specimen, the 

 largest tooth of the right paramere is apically bifid, but I can see 

 no such incision on the other side. This complex armature is very 

 curious, and I have so far seen nothing like it in any other earwig. 



The proparameres are dilated externally, and broad (PI. IX. figs. 

 3 and 4). 



Sub-family 2. Psalin.-e. 



As Zacher has observed, this group, which is a homogeneous 

 and extensive one, offers the greatest difficulties to the taxonomist. 

 The species are so numerous, and the number of new genera rela- 

 tively so great, that it is more convenient to deal with it separately 

 in a distinct paper. 



Sub-family 3. Labidurin^. 



The genital armature in this group is characterized by the more 

 or less parallel-sided, narrow, acute parameres, with long serpen- 

 tine virga having a basal vesicle with spiral structure. The genitalia 

 of the genus Tomopygia Burr has not yet been examined, but the 

 other three genera can be arranged as follows : — 



1. Metaparameres with epirnerit at apex. 



2. Metaparameres rounded and slightly widened 



at the apex . . . . . .1. Labidura Leach. 



2,2. Metaparameres lanceolate . . . .2. Forcipula Bol. 



1, 1. Metaparameres without epirnerit, acuminate . 3. Nala Zacher. 



In Labidura we may possibly find a means of defining as 

 species some of the forms of Labidura riparia Pall., which at 

 present I regard as variants of one highly plastic polymorphic 

 species. Zacher figures the genitalia of L. bicolor Kirby, from 

 Colombia, in which the metaparameres are broadly rounded at the 

 apex. In the Indian L. bengalensis Dohrn the curvature is much 

 more marked on the outer margin, and a small point is formed 



