286 
FASCICULI MALATENSES 
Messrs. Annandale and Robinson have now brought from the Malay. 
Peninsula a series of twenty-four individuals of Heliocopris^ which, after repeated 
examination, I believe to be all one species, and the one I described as H. mouhotus 
There are eight females, three large males agreeing with the large male of //. 
mouhotus (as previously known), in addition to three other males* which agree 
sufficiently well with the male type of H. dominus^ Bates, to make me feel 
doubtful whether they are distinct therefrom. 
By the kindness of my friend, M. Rene Oberthur, of Rennes, I have 
also before me eleven other specimens of these forms from Siam, Upper Burma, 
Rungpore, and Trichinopoly. They include the types of H. dominus and H, 
mouhotus^ and, on the whole, confirm the opinion I am now putting forward, 
that the two are really only one species. 
There is, however, one point of considerable interest to which I must call 
attention, viz., that there are no specimens intermediate between the two- 
horned large form (fig. A) I called H. mouhotus^ and the four-horned large 
male. Bates called H. domina (fig. B). If, therefore, I am correct in 
considering all the forms to be one species, it would appear that the form A 
is a very remarkable case of abrupt variation. It is, indeed, difficult to 
see how there could be a form intermediate between the A and B of our 
figures. C is clearly only a diminished or depauperated form of B. 
But B could only be made into A by pushing the two middle horns apart 
from one another, so that each became joined to the lateral horn on the same 
side, thus making two thick horns instead of four smaller ones. 
I imagine that something of this kind really happens in the course of 
the ontogeny of the large two-horned individuals, and if so, it is clear that 
not only have we at present no intermediate between the two forms, but also 
that we are not likely to find such, except as teratological specimens in which 
the coalescence of the horns is arrested before it is completed. 
I may remark that we know nothing as to the Natural History of these 
large forms, though I am informed by Mr. Annandale that they frequent the 
dung of elephants. 
The localities for the specimens of Messrs. Annandale and Robinson 
are both near Patani, viz. : — 
Ban Sai Kau, Nawngchik. May, 1901. 
Biserat, Jalor. October, 1901. 
I may add that I have hesitated much about coming to a decision in this 
question, and that the evidence as to the conspccificity of H. dominus and 
mouhotus is not quite convincing, because of the fact that few individuals of 
I. The other ten males are of less perfect development, and do not contribute any important evidence. 
