450 RHYNCHOPHORA. [ Platypodine. 
sides of the thorax and the round subconvex eyes ; the head is large, not 
covered by the thorax, and the labrum is small but distinct; the 
antenne are very short and have a large scape and a large compressed 
solid club, which is pubescent except for a small space at base; the 
thorax is rather long and the prosternum is moderately long in front of 
the coxee which are large, conical-cylindrical and oblique ; the meta- 
sternum is very long; the ventral segments are five in number and un- 
equal; the elytra are elongate and cylindrical and sloped or subexcavate 
at apex; the legs are short with the femora dilated, the tarsi long and 
slender and the claws simple. 
The larve of the genus Platypus differ somewhat from those of the other 
Scolytide, as may be seen by comparing Westwood’s figures (Classifica- 
tion I. p. 350, fig. 42, 4, 14, 22); the head is large and the body short 
and straight and not curved towards the extremity, where it is somewhat 
obliquely truncate, and the sides of the body are furnished with rows 
of distinct tubercles; the pupa is elongate with the intermediate 
coxe very large, considerably larger than in the ordinary Scolytid 
upe. 
i The life history of Platypus cylindrus has been very fully described 
by Dr. Algernon Chapman (Ent. Monthly Magazine, viii., pp. 103— 
182); the following account is abridged from “his observations, which 
are exceedingly valuable ; ; the beetle burrows into solid wood, and, in 
consequence, is difficult to observe ; these burrows, in which both per- 
fect insects and larve are found, have always an extremity open on the 
side of the stump; they are of uniform diameter throughout, viz., that 
of the full-grown larva and perfect beetle,—presenting no narrow 
burrows of young larve, as observation of most of the other Xylophaqa 
would have led us to expect ; and the inhabitants are not confined each 
to its own branch of the burrow, but the larve, to the number of from 
sixty to a hundred, together with the perfect beetles, their parents, run 
actively backwards and forwards in the burrows, and from one branch to 
another, getting out of each other’s way, backing into a branch to let 
another pass, just as a train is shunted into a siding, The usual 
habitat of Platypus is in oak stumps, but it also occurs in beech ; it only 
attacks stumps that have entered on their first period of decay, but are to 
all appearance sound ; the chief, essential appears to be the presence in 
the wood of a certain fungus, which probably lives in the fermenting 
and decomposing sap, and which half fills the galleries in which the eggs 
are laid, and serves as food for the young larvee. 
During July and August the beetle emerges from the pupal state, the 
greater number during the last week in J uly, and at this period ‘they 
commence their burrows ; occasionally an odd burrow is found, but 
usually the burrows are in colonies, and as many as fifty entrances may 
be found on the side of a stump scattered over a surface twelve to fifteen 
inches wide and four or five high; the burrow from its mouth on the 
surface of the stump isa perfectly clean cut cylinder. 
