Anatomy of the Male Genital Tube in Coleoptera. 505 
ring-like basal-piece, broader on dorsal than on ventral aspect, with 
a pair of narrow, pointed lateral lobes pressed close to the sides of 
the median lobe. The internal sac not large, but with complex 
armature at apex (53a, 53b). A flat, curved median chitin-piece (0) 
is attached to the internal sac by a large chitin knob (c) through 
which the ejaculatory duct runs and opens on the end of the median 
piece ; a chitin plate (d) with a second chitin knob (e) gives it greater 
support. To each side of the chitin knob (c) is attached a flattened 
pointed process, thickened at its base at the point of attachment, one 
is slightly longer than the other. 
Clambus minutus (Pl. L fig. 54). 
Median lobe a thin, partly flattened, tube, with the dorsal distal 
part drawn out into a curved process hooked at the tip, the ventral 
distal part into a semi-membranous tongue. The lateral lobes are 
amalgamated for two-thirds of their length and form a broad shallow 
plate with the distal third forming unequal points, bearing a couple 
of stout spines. The basal-piece ring-shape (bp). Internal sac not 
examined. 
Among the Silphidae s. 1. that we have examined there 
are three distinct types of aedeagus. The first is repre- 
sented by Sil/pha, in which the median foramen is small, 
the median lobe collapsible on the dorsal aspect and forms 
a collapsible bulb by means of which the internal sac is 
evaginated by fluid-pressure, and the sac bears no chitinous 
armature. In the second the median foramen is large, 
and the median lobe is not collapsible and does not function 
as a bulb for the evagination of the sac, and the sac bears 
chitinous armatures. 
The third type has the lateral lobes amalgamated to- 
gether to form one piece, and the median lobe is tubular 
and not collapsible. 
These characters do not quite agree with the divisions 
into families of the Silphid allies. As, however, the recent 
authorities are not in accord on this point, and as we have 
studied a very small percentage of the known forms, we 
have treated the assemblage as one family. But we hope 
our doing this will not be interpreted as supporting either 
one view or the other. 
The Silphid type approaches the Staphylinid type, but 
the presence of a reduced basal-piece serves to distinguish 
the two. 
