Genera of the CossonidcB. 519 
19. Tychiosoma {nov. gen.). — The insect for which I 
have founded the present genus is from the PhiHj)pine 
Islands, and has been communicated by Mr. Pascoe. It 
is very closely allied to the Japanese Tychiodes Adamsii, 
— from Avhich, however, it differs in being not only larger 
and more depressed and with the limbs longer, but like- 
wise in having its antennfe more medially inserted, with 
the scape especially more lengthened, less arcuate, and 
without any tendency to be hollowed-out internally, and 
with the funiculus gradually much more widened, and 
consequently Avitli the club (which is itself longer) less 
abru]3t. In addition to which, its prothorax (which is 
equally small) is more triangular, or less transverse, as 
well as (together with the under-segments) extremely 
shining and almost unsculptured ; its prosternum is 
clothed, between the anterior coxEe, with fulvescent pile ; 
and its front tibia? (instead of being simple) are slightly 
scooped-out towards their inner apex, the emargination 
being barbed posteriorly with strong fulvescent hairs. 
20. Leptomimus {nov. gen.'). — The tAvo species now 
before me for which the present genus is established, and 
which have been communicated by Mr. Pascoe as having 
been obtained by Mr. Wallace in the island of Gilolo, of 
the Malayan archipelago, combine many very curious 
featvu'es which are essentially their own. In their bodies 
being exceedingly narrow and parallel they agree with 
Stenotrupis ; but they nevertheless entirely want the 
elongate, thickened, exserted head, and the completely 
depressed eyes, of that genus ; their rostrum too is very 
much more lengthened and slender {not being subdilated 
anteriorly) ; their prothorax and antennae, as well as their 
second funiculus-joint, are much more elongated ; the 
third articulation of their feet is more expanded and 
bilobed ; and their legs (instead of being equidistant from 
each other at the base) have the intermediate coxjb rather 
widely separated, but the front and hinder pairs appreciably 
(and equally) more approximate. This last-mentioned 
peculiarity is rather anomalous amongst the Cossonidce, 
and particularly so amongst the Pentarthrides. In other 
respects Leptomimus is remarkable for the opake, reddish- 
brown, and most closely sculptured surface of its two 
hitherto-discovered exponents, — one of wdiich, moreover, 
is clothed with a short, setiform pubescence, whilst the 
other appears to be bald. In all probability the group 
