452 
INSECTA. 
They live under the bark of trees. The animal figured by Paykull, 
as the larva of a species of this subgenus, is that of a species of Syr- 
phus, or Fly* * * § . 
The other Histeroides, in which the preesternum j^rojects over the 
mouth, the maxillae are terminated by a short lobe, with but slightly 
projecting palpi composed of joints which, the last excepted, are 
rather in the form of a reversed cone than cylindrical, and finally, in 
which the mentum is slightly emarginated, will re-enter the subgenus 
H 1 ST: -Ev., properly so called. 
Some species in which, as in the Hololeptae, the foiir posterior tibiae 
have but a single range of small spines, and that also live under the 
bark of trees, constitute the genera Platysoha and Dendrophilus 
of Leach. The first f only difters from the second in the flattening 
of the body above, and in the shortening of the thorax, which is also 
narrowed anteriorly. A species of the same AWision, H. probosci- 
deus, Payk., Monog., VIII, 4, has a peculiar form. The body is long 
and narrow, and the thorax moi'e than half as long again as it is 
wide. 
The remaining Histeroides have two ranges of spines on the four 
posterior tibiae. They are the only ones which Dr. Leach retains in 
the genus Hister. 
H. umcolor,h.-, Payk., Ib., II, 7- Four lines in length; en- 
tirely black and glossy; three dentations on the exterior side of 
the two first tibiae ; two striae on each side of the thorax, and 
four on the external part of each elytron, that nearest the mar- 
gin interinipted. Very common. 
The number of tibial dentations, that of the striae on the thorax 
and elytra, their punctures, and the form of the body, have furnished 
M. Paykull with excellent characters, by means of which he has well 
described the species. 
A last subdivision of this tribe comprises very small Histeroides, 
with a thick and almost globular body, of which the but slightly or 
not at all laterally compressed praesternum does not advance over the 
■•^cjuth, and is straight in front. 
In some — Abr-EUS, Leach — it is prolonged to the anterior angles 
of the thorax, and entirely covers the antennae when they are con- 
tracted; in the others — Onthophilus, Leach — it is narrower; but 
here the antennal club is received into a very distinct orbicular cavity, 
situated under the anterior angle of the thorax. I'he anterior tibiae 
are frequently narrow, almost linear, and edentated. The last supe- 
rior semi-segment of the abdomen is curved inferiorly, and aj^pcars 
to terminate it§. 
* Hist. Monog., p. 101, et seq. 
-)- Hisfer picipes, Fab.; Payk., Ib., VIII, 5; — i/.yfai'iVoniw, Id., VIII, C ; — //. 
ohlonyus, Id., X, 3. 
X A. punctarus, Id., VII, 5. 
§ The U. ylobosus, Payk., VIII, 2, is referred by Leach to his genus Ab}'(eus, and 
also the H, minuttis, Id., VIII, 1; to his Onthophilus, he refers the Hist, siriatus, 
