Genera and Species of Coleoptera. 41 
clusions in regard to the limits or characters of natural groups from 
the examination of the species of a particular region only. M. 
du Val excludes Sylvanus and the cognate genus Nausibius from 
Cucujide because their tarsi have not the short basal joint which 
the remainder of the European members of this family possess ; and 
to this character he attaches an importance of the highest order, so 
that for him none others are Cucujide ; but if we look to the well- 
known genus Palestes (and still more to Zpsaphes just described), 
to Platisus, or to Scalidia and Ancistria, where the basal joint far 
exceeds in size and length those which follow, we shall see at once 
the utter futility of this character. I think, too, it shows how 
cautious it is necessary to be before we take what may prove 
to be a mere technical character for one of real natural import- 
ance. The division of the Cucujide according to the difference of 
number of the tarsal joints in the two sexes is also objectionable. 
Pristoscelis*, which can scarcely be distinguished otherwise from 
Peediacus, is pentamerous in both, and would therefore be placed by 
M. du Val with Monotomine ¢. With regard to Synemis, we must, 
I think, for the present consider it an isolated genus. The number 
of these insects, which conceal themselves under bark and in the 
-axille of leaves, is probably enormous. They are generally minute, 
and are not often sought for, and we must therefore expect to find 
a form turning up now and then whose affinities are uncertain. 
The posterior tibie and tarsi of Pristoscelis (accurately described by 
Mr. Wollaston, but as to the tarsus most inaccurately represented 
in the figure) are to a certain extent repeated in Synemuis; it has 
also the hooked inner maxillary lobe of that genus. I owe this 
most interesting form to Mr. Bowring, who took it in considerable 
abundance at Penang, in the axille of the leaves of a species of 
Pandanus. 
Synemis pandani. (Pl. III. fig. 8.) 
S. fusco-testaceus, nitidus; prothorace vage punctato; elytris punctato- 
striatis. 
Hab, Penang. 
Elongate, very narrow and depressed, chestnut-brown, subnitid ; 
head nearly plane, oblongo-subquadrate, a little broader behind the 
eyes, sparingly punctured ; antennze remote from the eyes, short, the 
basal joint thickened, as long as the next two together, the remainder 
* This name has been preoccupied by Dr. Leconte for a genus of Dasytine. 
+ Monotoma, according to M. du Val, has 5-jointed tarsi, and he therefore 
places it with the Cucujidz. 
