160 staphylinid;e. [Agaricochara. 



than in any of the G;iroph(:enm except O. dridula, impunctate ; an- 

 tennae rather long ; thorax very short, ninch narrower than elytra, 

 almost impunctate, but, together witli head, finely shagreened ; elytra 

 much longer and broader than thorax, finely and sparingly, but distinctly, 

 punctured ; hind body almost smooth, or obsoletely shagreened ; legs 

 testaceous. L. 1 mm. 



The sexual differences do not appear to be important. 



In boleti growing on old stumps and trees; local ; London district, rather common ; 

 Hampshire; Yardley and Knowle, near Birminijham ; Buddon Wood, Leicestershire; 

 Repton ; Sherwood Forest ; Scarborough ; Manchester district ; Northumberland 

 district, rare, North Seaton and Ravensworth ; not recorded from Scotland. 



PXiACVSA, Erichson. 



ft 



This genus contains between twenty and thirty species, the majority 

 of which are found in Europe : it is probable that the genus has a very 

 wide distribution, as, although two or three species only besides the 

 European species have hitherto been known (from Cejdon, Australia, 

 &c.). Dr. Sharp has lately described no less than nine new species from 

 Central America ; the species are small and obscure, and live under the 

 bark of dead trees and logs : they are also found at sap ; the male 

 characters are peculiar, and in many cases afford helps to identification, 

 but otherwise the species are very hard to distinguish ; the synonymy is 

 in consequence very confused, and it seems hardly settled how many 

 species we really possess as British. 



The larva of Placusa pumilio is described by Perris, Ann. Fr. 1853, p. 565, pi. 17, 

 fig. 20-25 ; it is about 3 mm. in length, entirely yellowish -white, with the head and 

 three last segments of abdomen spotted with reddish markings ; the general shape 

 calls for no particular observation ; the 8th segment of the abdomen is quadrate, 

 narrower than the 7th, and the 9th is much narrower than the 8th and bears a short 

 anal appendage and two short cerci, the 2nd joint of which is a little longer than 

 the 1st. 



This larva, like that of Phloeopora reptans, appears to prey on the pupse of Tomicus 

 and probably on their larvce ; it transforms itself into a soft white pupa in the middle 

 of the detritus with which they fill their galleries. 



I. Thorax at base fully as broad as elytra ; upper surface 



duller, 

 i. Size smaller ; antennae with joints 5-10 strongly 



transverse, about equal in length P. PUMILIO, Grav. 



ii. Size larger; penultimate joints of antennae a little 



more strongly transverse than the preceding ... P. complanata, Er. 



II. Thorax at base slightly but distinctly narrower than 



elytra ; upper surface more shining. 

 i. Size smaller ; spines on each side of 7th segment of 



male short P. infima, Er. 



ii. Size larger; spines on each side of 7th segment of 

 male long P. denticulata. Sharp. 



P, pumilio, Grav. Of a dull black colour Avith the elytra and apex 



