124 MACDOUGALL—ON THE LIFE-HISTORY 
power of making galleries in every direction will facilitate 
their moving about in the search for prey. 
The perfect beetle, found in conifer woods running over the 
bark of standing or felled trees, is also carnivorous, subsisting 
on destructive bark-boring insects. In the month of July I 
introduced a live Clerus (bred out of one of my pieces of pine- 
bark) into a glass tube which held four live Wylesinus palliatus. 
This Aylesinus palliatus is a small and destructive beetle which 
makes crutch-shaped galleries below and in the barkof pine and 
spruce and larch. For a quarter of a minute the C/erws ran 
up and down the inside of the glass, and then pounced upon 
one of the Ay/esinus, seizing it in the weak spot in its armour, 
viz., on the under surface where the head is jointed on to the 
thorax. I lifted the tube to examine the more closely what 
would follow, lens in hand, when the C/erus started to run up 
and down the sides of the tube, and though it lost its footing 
several times and fell to the bottom, never for a moment did it 
let go its victim, whose antennz were seen to be quivering 
nervously. At last, coming to rest, and propping itself on its 
two hind legs, the Clerus held the Hyesinus up to its mouth by 
means of the four front legs—a position also recorded by 
Ratzeburg.* First of all, the head of the victim was bent 
back and emptied by means of the jaws, and then the hind 
part of the body gutted in the same way. Finally the elytra 
were broken off and the wings torn to shreds. 
In watching C/erus feed at different times, I noticed that the 
seizure of the prey was always at the same place viz., between 
the head and the rest of the body. After a meal the beetle 
seemed to spend some time in cleaning itself, pulling its 
front oe through its jaws and the front legs over the 
antennz . 
Late one evening in July I placed in one tube three live 
Hylesinus palliatus and one Clerus, and in another tube seven 
live Hylesinus palliatus and one Clerus, Examination next 
_ evening showed that all the three Hy/esinus in the first tube 
had been devoured, and five out of the seven in the second 
tube were only represented by scattered fragments of their 
external parts 
No records seem to exist as to the length of life of Clerus 
