11 
we have obtained a specimen identified by Mr. Edm. Keitter as bicornis 
Er. Judging alone by this single example and the fact that I have 
examined fully three hundred individuals of Silvanus with saw-toothed 
thorax, brought together for the purpose, witbout finding anything even 
approaching it, I am much inclined to believe that this specimen is not 
a male of surinamensis, but whether or not it is the true bicornis of* 
Erichson someone having access to the original description or the 
types may decide. 
Judging by M. Guillebeau's description and our single specimen, 
bicornis differs from surinamensis chiefly by the side margins of the 
front in the male being more strongly reflexed, forming on each side a 
prominent horn, and by the scutellum being at leas* three times" as wide 
as long and scarcely rounded behind. In surina- 
mensis these reflexed portions of the front are of 
decidedly different appearance, and can hardly be 
termed horns. The scutellum is less than twice as 
wide as long and distinctly rounded behind. In the 
male before me the horns are very thin, much flat- 
tened, and concave dorsally, like the pointed ears of 
some mammals in outline, and distinctly incurved at 
the apex. (See fig. 2.) This male measures 3 mm., 
or about as long as the largest surinamensis. 
Erichson described his species from Tyrol and 
Sicily. Our specimen is from Kaifa, Syria. M. Guillebeau states that 
this species is extensively distributed in France, and that it was taken 
in wheat granaries at Orleans, and in a dried fig at Lyons, showing 
it to have similar feeding habits to surinamensis. It would naturally 
be called the two-horned grain beetle. 
In more recent years several other species of Silvanus of the surina- 
mensis group have been discovered. 
The first of these is denticollis, described by Keitter in 1876, from 
Ceylon (Harold's Coleopterologische Hefte, Vol. XV, p. 50). It di tiers 
from all other known species of this group in having the head without 
tempora and the disc of the thorax without sulci. 
In 1889 M. A. Fauvel described mercator from France. •• Africa," and 
New Caledonia. (Revue d'Entomologie, A^ol. VIII, p. 132.) 
The following year M. Guillebeau brought together in synoptic form 
all the above-mentioned species, with abcillci, described as new from 
Palestine (1. c, Vol. IX, pp. 220-224) and later in the same year Reiner 
also furnished a synopsis of these species, describing fauveli from 
Syria. (Wiener Rut. Ztg., Vol. IX, pp. 255-250.) 
Fig. 2.— Silvanus bicor- 
nis— enlarged (origi- 
nal). 
