502 Mr. D. Sharp and Mr. F. Muir on the Comparative 



Micropeplus fuhus (PI. LIV fig. 74). 



This is a Staphylinid type, the median lobe being large and 

 bulbous at the base ; the median orifice at the apex large, the 

 median foramen small and one-fourth from base on ventral side. 

 The lateral lobes are so completely amalgamated to the median lobe 

 that it is very difficult to distinguish them, but they are of fair size 

 and lie along the ventro-lateral portion of the median lobe. The 

 internal sac is large, complex, covered with small chitinous spines 

 and supported by chitinous patches. 



It is among the Staphylinidae that we have found the 

 greatest modification of a single type. In this family the 

 internal sac reaches a high state of specialisation and the 

 modification of the median lobe for the evagination of the 

 sac by blood-pressure is carried to perfection. This is 

 biought about by modifying the tubular median lobe into 

 a bulb having chitinisations on the dorsal and ventral 

 aspects, with a band of membrane between, so that the 

 dorsal and ventral sclerites can be brought together by 

 muscular contractions and so exert pressure of a fluid on 

 the sac and turn it out. 



The Staphylinidae are distinguished from the Silphidae 

 by the absence of a basal-piece. Since our paper was 

 written Dr. L. Weber of Cassel has published a very 

 valuable paper on the male genitalia of Staphylinidae 

 (Festschr. Ver. Cassel, 1911). We are, however, not pre- 

 pared to accept his interpretation of the very abnormal 

 genus Habrocenis, as to which he himself speaks with 

 considerable diffidence. 



Family SILPHIDAE ( = families Silphidae, Liodidae, 

 and Clambidae, Reitter). 



Forms examined : Silpha (Phosphuga) atrata L., Eng- 

 land. S. obscura L., England. S. j'aponica Motsch., 

 Japan. S. ? analis Chevr., Panama. Necrodes osculans 

 Vig., Woodlark Island. Necropihorus mortuoruni Fabr., 

 England, Astagobius angustatus Schm., Carniola. Ba- 

 thyscia (sp. not in Brit. Mus.), Piedmont. Liodes (Anisotoma 

 of certain authors) humeralis Fabr., England. Clambns 

 minutus St., England, 



Figs. 48-54, Plates XLIX and L, are devoted to this 

 group. 



