502. Mr. D. Sharp and Mr. F. Muir on the Comparative 
Micropeplus fulvus (Pl. 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 
brought 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 Habrocerus, as to which he himself speaks with 
considerable diffidence. 
Family SILPHIDAE (= families Si/phidae, Liodidae, 
and Clambidae, Reitter). 
Forms examined: Stlpha (Phosphuga) atrata L., Eng- 
land. S. obscwra L., England. 8S. japonica Motsch., 
Japan. S.? analis Chevr., Panama. Necrodes osculans 
Vig., Woodlark Island. Necrophorus mortuorwm Fabr., 
England. Astagobius angustatus Schm., Carniola. Ba- 
thyscia (sp. not in Brit. Mus.), Piedmont. Liodes (Anisotoma 
of certain authors) humeralis Fabr., England. Clambus 
minutus St., England. 
Figs. 48-54, Plates XLIX and L, are devoted to this 
group. 
