156 Proceedings of the Royal Physical Society. 
Hylastes palliatus, 
The damage done to the forest by H. ater and H. cunicularius is easily 
observed, and the financial loss is not difficult to estimate. This is not the 
case with H. pallatus. It occurs in older woods, and on the stems and 
crowns of the trees whose foliage is lost in the ceneral canopy, so that sickly 
and even dead trees are easily overlooked. H. pallatus, moreover, is 
usually a follower of the Pine Beetle, JZ. piniperda, and where it is obvious 
that a tree has been killed by these two beetles, it is not always easy to 
determine what part either of them played in its destruction. This difficulty 
is of less common occurrence in spruce woods, but, on the other hand, the 
fungus, Fomes annosus, may cause a kindred difficulty. 
I have, unfortunately, been unable to observe the development aiid 
termination of an attack by H. palliatus in our woodlands, and must content 
myself with giving a general account of my various observations made from 
time to time. Unlike its congeners, H. pailiatus is harmful both in the 
larval and in the adult stages. Its galleries restrict the sap flow and reduce 
the vitality of the attacked tree, or, if numerous, stop the sap flow and kill 
the tree. H. paliiatus rarely attacks vigorous healthy trees. It prefers 
trees weakened by squirrel attack, by smoke damage, or by suppression, by 
lack of light, by fungus, by the attacks of the Pine Beetle, M. piniperda, 
and by the lesser Pine Weevil, P. pint. It is a secondary pest. Owing, 
however, to its occurrence in large numbers, it 1s not improbable that in 
certain cases it ranks in point of destructiveness with MM. puniperda. In 
plantations at Skene, Aberdeenshire, and on Earlyvale, Peeblesshire, I have 
found H. palliatus predominating over JZ. puperda and proving decidedly 
more harmful. ae . 
As a rule, H. palliatus is of less importance as a forest pest than its 
congeners ater and cwnicularvus. It attacks trees at an age when they are 
better able to overcome attack, and, moreover, trees killed by A. palliatus are 
still useful as timber. The loss caused by H. palliatus is purely a loss of 
increment or interest, the loss caused by its congeners is a loss of interest and 
capital as well. | 
Preventive and Remedial . Measures—The question of preventive and 
remedial measures is too complex and debatable to be dealt with in 
this paper. It is intimately bound up with our Scottish system of forestry 
and even with our land legislation. In the writer’s opinion, prevention of 
insect attack is as much the concern of the silviculturist as of the 
entomologist, and until forest protection is properly recognised in this — 
country as a real and necessary branch of forestry, little can be done in 
that direction. Pate 
