596 Mr. D. Sharp and Mr. F. Muir on the Comparative 
tusks of the lateral lobes slightly shorter, and the consolidation of 
the two lobes where they meet in the middle behind the ventral 
plate very short. 
One example (Cochin China, old coll.) of the same development 
as the two moderate Koberi forms, differs from them in having the 
ring of the lateral lobes considerably narrower, the tusks a little 
longer, and separated by an interval of rather different form. The 
difference from the Koberi high development male is even slighter. 
One specimen from Amboina (F. Muir), a small development but 
not the smallest, has a decidedly different shape of the orifice, which 
may be described by saying that above it resembles a Gothic arch, 
while the forms previously mentioned are more like a Norman arch. 
Still more striking is the fact that the membrane above and in front 
of this arch is strongly chitinised, quite black, and the ventral plate 
is extensively chitinised. 
One specimen (“ Malasia,” old coll.) of maximum development 
as regards cephalic and thoracic armature, but a rather small and 
slender individual, differs shghtly from the Koberi moderate form 
in having the distal cylinder of the tambour more slender, and as a 
consequence the orifice between the lateral lobes more contracted ; 
the tusks are a little longer, and the area between them is narrower 
and of slightly different form. 
An individual (“ Ter” [nate] Wallace I believe) is of almost the 
smallest development of the species, being with cephalic horn only 
about 30 mm. long ; it approximates the Amboina individual, but 
entirely lacks the hard chitinisation of that specimen. 
The sac, in these examples, has not been adequately examined, 
but in the specimen from Cochin China the curious pair of large 
spines on it appear to be more inequal in size than they are in the 
others. 
Whether any racial distinctions are to be found in these male 
structures can be decided only by the examination of good series. 
We see no reason for supposing that any of the distinctions are of 
specific importance. The extreme chitinisation of the parts in the 
Amboina individual is remarkable. In it and in the Ternate example 
the two spines on the sac are nearly of one size. 
Augosoma centaurus. 
Very like X. gideon but the points of the lateral lobes are acute, 
and pressed together to their tips and turn downwards; the 
ventral plate of the basal-piece is consolidated to the lateral 
lobes ; the internal sac is large and has no spines, but has at least 
one long diverticulum, The conjoined struts at the base of the 
