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



pointed apices, consolidated together for the greater part of their 

 length. Basal-piece small, symmetrical, with the opening on the 

 ventral (?) face. 

 This comes near to Sphaerites. 



Family NIPONIIDAE. 



Form examined : Niponms canalicollis, Japan. 

 Fig. 82 PI. LV. 



Niponms canalicollis (PI. LV figs. 82, 82a). 



Median lobe tubular, slender and long ; lateral lobes longer than 

 median lobe and enveloping them. Basal-piece forming a long tube, 

 constricted near its base and bent. Internal sac undifferentiated. 



This form of aedeagus is nearest to Syntelia but differs 

 in having the tubular basal-piece long, a character in itself 

 not of family importance. 



Family HISTERIDAE. 



Forms examined : Hister cadaverinus HofFm., England. 

 Pachylister chinensis Quens., China. Macrolistcr mnximus 

 01., Africa. Oxysternus maoiimus L., Guiana. Holohpta 

 elongata Er., Andaman Islands. H. arcifera Mars., 

 Cameroons. Saprinus nitiduhis Fabr., England. Teretri- 

 osonia stebhingi Lewis, India. 



Figs. 79, 80 and 81, PI. LV, relate to Histcridae. 



Hister cadaverinus (PI. LV figs. 79, 79«). 



Median lobe well developed, chitinous, slightly curved, with a 

 large flange running round the lateral and distal edges of the 

 apical half (a), forming a cavity in which the apical armature lies 

 when the median lobe is at rest. This median armature is a pair 

 of two-pronged structures, amalgamated at their bases and articu- 

 lated to the base of the median lobe ; when the median lobe is 

 withdrawn between the lateral lobes at rest, the armature lies in 

 the cavity, but when it is thrust out the armature turns back. 

 There is a pair of short median struts. Tegmen consisting of a 

 small basal-piece with very large lateral lobes amalgamated on 

 their ventral side to the tip, and on the dorsal side along the basal 

 half. Internal sac undifferentiated. 



Macrolister max>:imits. 



A figure is given of this with the median lobe erected (PI. LV 

 fig. 80V 



