Part V] Beeson: Larvae and Life Histories of Prionine Beetles. 9 
JProsternum punctate, the punctures each with a short brown hair; 
eusternal and presternal region divided into 3 subequal triangular areas, 
by two oblique sutures. 
Thoracic spiracle twice as long as that of first abdominal segment. 
ABDOMEN. Ambulatory ampullae (Pigs. 5, 6) smooth, dorsal 
series decreasing in breadth and increasing in length from the 1 st to the 
5th segments, the 5th and the 6th equal, 7th about equal to 4th; 
transverse impressions, parallel, very slightly curved posteriorly, 
truncated by two intersecting lateral impressions; ventral series with the 
progressive decrease less marked; the single transv rse impression arcuate 
forward; (in living larvae both dorsal and ventral surfaces are deeply 
grooved by a median longitudinal furrow). 
8th abdominal segment cylindrical, equal in depth to preceding. 
9th abdominal segment more than twice length of 8th. 
Anus with the margin protuberant round a Y-shaped suture. 
Length of largest larva 50 mm.; Breadth of thorax, 13 mm. 
Notes on the Life History. 
On the 9th February 1915, larvae of M. plagiata were collected by 
the writer in galleries in the large buttresses at the base of a dead sundri 
(S. T. 77) ; the larvae varied in length from 13 mm. to 37 mm. 
A log [ RRD. 5, B. C. R. 2 ] was despatched to Dehra Dun and 
caged on 10th March 1915. 
In 1915 two male beetles emerged, one on the 30th June and the other 
on the 2nd July. A portion of the log was examined on 14th August 
1915, and no living insects found in it. On 18th November 1915 the 
remaining portion was examined and three small larvae of M. plagiata 
removed, and the log replaced in the cage. 
In 1916 two more beetles emerged, one ? on the 30th June and one 
c? on the 16th August. The experiment was discontinued on the 9th 
June 1917 in error, but emergence holes in the log show that one beetle 
emerged in 1917 subsequently to this date. 
On 12th September 1918 the log was cut up and one living larva 2J 
inches long found in a gallery. 
It is thus apparent that the life cycle of Macrotoma plagiata varies 
from one year to at least 5 years; the abnormally extended larval period 
is due in all probability to the desiccation of the wood on which the larva 
is feeding. 
[ 105 ] 
