PLOCEDERUS OBESUS. 369 

antennz is large and swollen, the remainder long and swollen at 
the nodes, where they are black; they are longer than the 
total length of the insect in @, of the same length or slightly. 
shorterin 9. The thorax has a transverse ridge at upper and 
lower edges and the vertex is covered with small raised irregular 
transverse ridges; the outer edges are produced into a spine 
medianly. The elytra have a distinct shoulder to the upper 
outer angle, the tips being truncate and spined. In the @ the 
last segment of the body projects beyond the elytra. The legs 
have 4 jointed tarsi, the 3rd joint is deeply cleft in a 
heart-shaped manner, the 4th joint being inserted in the cleft 
near the upper end of the third. Length 14-1} inch, 
Life-History, 
The following observations made in the Siwalik forests in the 
United Provinces practically complete the life- Sa of this 
insect for Upper India. 
The beetles appear on the wing in March and soon after 
pair and lay eggs in the bark of either sickly or freshly felled 
trees. From these eggs small grubs hatch out in April and feed 
for a time in the bast layer, making winding galleries in the bark 
and sapwood. As the larve increase in size and their mandibles 
become stouter they bore down through the sapwood and spend 
the rest of this stage of their existence in the heart-wood of the 
tree. About August-September the larva is full-fed and changes 
into the pupal state within the curious calcareous cocoon peculiar 
to this insect (see /njurious Insects, p. 68 and Pl. III, fig. 3¢). 
This takes place at various depths in the tree. If some of these 
‘cocoons are broken open at the end of November, the fully 
developed beetle will be found inside them, mature but not ready 
for flight as its outer covering is still soft. The pupal 
state is evidently a short one, but the beetle on maturing rests 
within the cocoon between December and March, whilst its outer 
parts are slowly hardening. If the insect is examined in 
December, it will be seen that the elytra are still quite soft, and 
that the legs and antennew are by no means ready to perform their 
respective functions properly. The beetle can walk but only in a 
