9 
dark metallic brown, and fresh specimens are coated here and there 
with a powdery gray substance, which is easily rubbed off. The wing- 
covers are ornamented as shown in the illustration, and underneath, 
as may be seen when the insect is in flight, the body is a bright metallic 
greenish blue. The under surface is coppery bronze. The males are 
smaller and may be further distinguished from the females by their 
green heads, as well as by other characters (see fig. 3, ¢). 
Unlike the round-headed borer the present species is diurnal in 
habit, being most active in the heat of the day and commonly found 
on prostrate trees and logs, or on injured trunks, basking in the sun- 
light. The beetles are active creatures, running rapidly and flying 
readily. 
This borer attacks diseased or dying trees by preference, inhabits 
all parts of a tree from the base of the trunk to the limbs, and is not 
restricted to fruit trees, but attacks a variety of deciduous trees, also. 
In all these respects it differs from the round-headed borer, but 
agrees with the latter in that it is injurious chiefly to young trees, its 
injuries being practically confined to newly transplanted nursery stock 
and to trees which have been weakened through any cause, such as 
careless pruning, or insufficient nourishment due to poor soil or 
drought. There is a difference of opinion as to the nature of damage, 
some writers taking the stand that healthy trees are not injured at all. 
It is a well-known fact that many forms of boring insects prefer injured 
plants, but when these are wanting do not hesitate to attack perfectly 
sound growth, and records show conclusively that the present species 
is included in this category. The general opinion is that trees suffer- 
ing from “‘sun scald” are most subject to attack, and the opinion has 
been expressed that injury known under this name is in reality due to 
the work of this borer. The beetle is essentially a sun-loving species 
and deposits its eggs almost exclusively on the southern or south- 
western side of standing trees or on recently felled logs that are exposed 
to direct sunlight. Observation leads us to have doubts as to the 
ability of the young larve to withstand the strong flowing sap of vig- 
orous trees. 
Infestation may be detected by the discoloration of the bark. 
A list of the recorded food plants of this borer includes, among 
orchard trees, apple, pear, and peach; and of shade and forest trees, 
mountain ash, oak, maple, box-elder, hickory, chestnut, sycamore, 
horse-chestnut, linden, and willow. To this list should be added plum 
Nore.—A third species of Saperda, fayi Bland, has similar habits and is likely to 
attack apple and similar cultivated pomaceous trees, but is thus far known only on 
thorn. A full account of this species was published by the late Dr. Hamilton (Can. 
Ent., Vol. XX, pp. 6-8). 
(Cir. 32] 
