CLERUS SP. 217 
Relations to the Forest. 
From the foregoing description of the habits of this beetle 
it will be seen that it is pre-eminently an insect of the greatest 
use to the forester. Itis avery easy beetle to recognize both 
in its larval and adult conditions, and it would be advisable, I 
think, that officials in charge of forests which it affects should 
endeavour to make themselves acquainted with it, Its discovery 
is one of some importance. Although perhaps a different 
species, it will not improbably be found to be closely related 
to Clerus formicarius, which is known to be of the very 
greatest service in keeping down bark-beetles in European 
continental forests. So great is the value attached to this beetle 
that in 1892 a specialist was deputed from America to import 
it into that country in the hopes of bringing down to normal 
proportions some devastating bark-boring beetle attacks. 
This Clerus was found upon the bark of deodar trees infested 
with the two Scolyfus barkeborers, and observations would 
tend to show that these latter beetles are to be found through- 
out the months from May to October. The reason is that they 
do not die off as soon as their egg-laying is finished, and it is 
possible that the first beetles from the larve hatching out from 
the eggs laid by them commence to issue before the mother 
beetles have all died off. In this way there would be a continued 
supply of Scolyéus beetles for the Clerids. 
But though this may be the case, I have ascertained that 
the Clerus does not confine itself to the Sco/ytus, I have fed it 
with the following beetles, all of which it eat with avidity : 
Platypus or Diapus sp., (Platypodz) from deodar wood. 
Tomicus sp. the Blue Pine Tomicus, 
Polygraphus major and P. minor from deodar and Blue 
pine. 
Pityogenes coniferz from deodar and Blue pine. 
It has also been found on the dan oak (Quercus tncana) where 
it feeds upon the Platypus, Diapus tmpressus, or a closely allied 
Q2 
species, 
