134 The Rev. W. F. Johnson and Mr. G. H. Carpenter 
LIFE-HISTORY AND HABITS. 
So far as we know the early stages of Pelophila have 
not hitherto been described. It seems worth while, there- 
fore, to place on record a few facts concerning the life- 
history of P. borealis which one of us has been able to 
observe during several years’ collecting in the neighbour- 
hood of Armagh, together with a detailed account of the 
external structure of the full-grown larva. 
The female beetle lays her eggs in the ground. They 
are hatched in the course of three or four days, and the 
erubs, when they first emerge, are white and soft-skinned. 
At the age of four days, the larva has attained a length of 
4 mm. and is covered with dark chitinous armour. The 
insect at this stage (Fig. 1) scarcely differs in structure 
from the full-grown larva, except for the very marked 
constriction at the seventh abdominal segment, and the 
simple form of the cerci (Fig. 2). At this early stage, 
these are fixed processes of the ninth abdominal segment, 
not mobile appendages as they become in the full-grown 
larva (Fig. 10). There are, moreover, but few nodular 
tubercles and sete, as compared with the complex arrange- 
ment developed at a later stage. 
By feeding the grubs on raw beef which they devoured 
ereedily, it was possible to rear them until they had 
attained their full growth. The time taken in completing 
the larval development was about a fortnight. Full- 
grown larve were subsequently discovered in well-known 
haunts of the beetle, their identity being placed beyond 
doubt by their correspondence with the grubs which had 
been reared from the eggs. Unfortunately none of the 
larvee pupated, as all those reared to their full size met 
with accidents. They seemed to devour their cast skins, 
as none of these were found, and one was observed 
devouring what appeared to be its cast skin. 
In their native haunts the habits of the larva are much 
the same as those of the perfect insect. They live on the 
borders of lakes and banks of rivers preferring a firm clay 
bank with plenty of loose stones lving on it. They are 
always found at a short distance from the water where 
the ground is moist, a condition which seems indispensable 
to their well-being. The larve are very active and run 
about quickly when disturbed. They hide under stones 
and they either wait for their prey there, or else pursue 
