296 STAPHTLINID/E. [OtJliuS. 



In moss, dead leaves, &c. ; not uncommon ; often confounded with tlie next species, 

 and considered by some authorities to be contiued to the north, our southern specimens 

 being all referred by them to O. wyrmccophilus : 1 have, however, undoubted examples 

 from Malvern and Yorkshire ; in Scotland the sjiecies is common as far north as 81iet- 

 laud, and it is recorded from Dublin, Waterford, Gal way, and Armagh in Ireland. 



O. myrmecophilus, Kics. Very closely allied to the preceding, 

 and chiefly distinguished from it by the shape of the head which is 

 evidently shorter, less oblong, and broader, being about as broad as the 

 thorax, instead of somewhat narrower as in 0. melanocei)! talus ; the 

 colour is considerably darker, and the thorax is pitchy brown rather than 

 red, but this is somewhat variable ; the thorax also is slightly more 

 parallel-sided. L. 5 mm. 



In moss, dead leaves, &o., sometimes, as its name implies, in company with ants 

 {F. fuliginosa, &c.), but this is by no means always the case, and, in fact, appears to 

 be rather the exception than the rule ; Mr. J. Chappell records it from Mancliester in 

 bees' nests ; it is widely distributed throughout the kingdom, occurring as far north 

 as the Shetland Islands. 



P^DEEIN^. 



This sub-family^ as at present constituted, contains about sixty genera; 

 it is divided into two groups, Latrobiaires and Pederaires, by Mulsant and 

 Eey on the formation of the penultimate joint of the tarsi, but this does 

 not seem more than a generic character at the most, and in some cases, 

 e.g. Stenus, is regarded merely as specific. In the Peederinse the anterior 

 and posterior coxse are conical and prominent ; the mandibles are long 

 and blender ; the last joint of the maxillary palpi is usually acute ; the 

 thorax is usually bordered at the sides, but not always, and is very vari- 

 able in form ; the hind body is bordered ; the head is rather large in 

 most cases, and is always contracted into a more or less narrow neck ; 

 the species are narrower and linear and have, as a rule, a very distinct 

 appearance ; some of them, e.g. those belonging to the genus Pcedems, 

 are very brightly coloured. The Evsesthetinee are not here included under 

 the Piaederinse, as they are by many authors ; the reasons for their separa- 

 tion as a sub-family will be found given in the remarks on the group. 



I. Penultimate joint of tarsi simple without any membranous 

 appendage beneath. 

 i, Antennse strongly geniculate, first joint forming a long 



scape CEyPTOBlUM, Mannh. 



ii. Antenna} not or only slightly geniculate. 



1, Anterior femora and tarsi very strongly dilated, 



A. Last joint of posterior tarsi about as long as the 



four preceding together ; body very flat . . . ACHENIUM, Curt. 



B. Last joint of posterior tarsi not as long as the 



three preceding together; body a little convex . Latheobium, Grav. 



2. Anterior femora and tarsi not at all or comparatively 



slightly diated. 

 A. Thorax slightly contracted in front, subquadrate. 

 a. Prosternum pn longed to form a process resting 



ou the front of the mesosternum Medon, Steph. 



