Cossonidce of Japan. 31 
apex.* And 
Heterarthrus is further remarkable for the puiictation of 
its head and prothorax being dense but at the same time 
fine, and for its elytra being more or less of a pallid hue 
(sometimes ornamented with a black patch), — an arrange- 
ment of colour Avhich gives the insects a totally different 
aspect from any of the other Cossonidce with which we 
have here to do. As regards the antennae, they are inserted 
either in the middle or just before the middle of the ros- 
trum; and the four posterior tibi^ are subflexuose and 
slender (particularly at their base), and less evidently 
armed at their inner apex. Their second funicidus-joint 
is (like the succeeding ones) short, and their club is large 
and abrupt. 
a. AntenncB mox ante medium rostri (yjpaulo longioris) 
insertoe. Pedes elongati. 
12. Heterarthrus Lewisii, n. sp. 
H. elongato-fusiformis, subnitidus, convexiusculus ; ca- 
pite prothoraceque vel nigris vel brunneo-nigris, dense sed 
argute punctulatis, hoc elongato-ovato, elytris vix angus- 
tiore; elytris fusiformi-cylindricis, basi anguste margi- 
natis, rufo-ferrugineis (interdum nigro-pictis), striato- 
punctatis (striis versus suturam profundioribus), inter- 
stitiis latis depressis subrugulosis et parcissime minutissi- 
meque (sub lente) punctulatis; antennis tarsisque plus 
minus piceo-ferrugineis, femoribus tibiisque plus minus 
piceis. Subtus leviter punctatus (punctis in abdomine 
fere obsoletis). 
Variat elytris plaga magna suffrisa post mediS. (antice 
per suturam versus scutellum angustius currente) nigres- 
centi-ornatis. 
Long. corp. lin. 2^. 
Captus prope Nagasaki, in ins. Kushlu. 
Species valde distincta, ornata, et in honorem cl. 
G. Lewis, insularum Japonicarum scrutatoris oculatissimi 
indefessi, citata. 
* This character, although real, is not a very easy one to observe, — 
inasmuch as when viewed laterally the joint seems to be equally clavate, 
and similar, in both sexes ; and it is only when inspected carefully from 
above, and beneath a high magnifying power, that the conical outline, in 
that of the females, becomes evident. And I may add that, since writing 
the above, I have remarked the same peculiarity of tarsal articulation in 
a Cossonid from Ceylon, which has been communicated to me by Mr. 
Janson, and which indeed I have every reason to suspect (without further 
examination) is a true Heterarthrus. 
