THE PINE BORER OR "SAWYER." 691 
The egg (Fig. 228, a) is very large, ovo-cylindrical, well-rounded, but 
but tapering somewhat at each end, of a dirty-white color, and in 
length is 4£ mm . 
On visiting the tree a week later and removing a portion of the bark 
and examining it, September 6-8, the eggs had in some cases hatched 
and the larvae had begun to descend slightly into the bark. On hatch- 
ing they begin at once to gnaw a mine, throwing their castings out 
through the gash originally made by the female, so that it was easy to 
ascertain without disturbing the bark whether the eggs had hatched or 
not. The larvae indifferently lie with either side, dorsal or ventral, pre- 
sented outwards. Three days after (September 12) several had bored 
through the pieces of bark, making the usual flattened oval hole, but 
probably in nature the larva remains hidden in the bark through the 
winter, not beginning to penetrate the wood until the following spring. 
The length of the larva when freshly hatched was o-6 mm , and the 
body was rather stouter than in the fully-grown larva. (Fig. 228, b.) 
How many eggs are laid by the female is not known, but, probably, 
judging by their large size, comparatively few. 
Another female was found on the same tree. Over a hundred gashes 
had been made on the western side of this fir tree over a space 4 feet 
long; the gashes were so fresh that they must have been made on that 
and the previous days. They were quite conspicuous, and could, after 
one had become familiar with their appearance, be detected at the dis 
tance of 5 or 6 feet from the tree. I suspect that the sexes couple 
frequently during the operation of egg-laying, as the male was stand- 
ing so near his mate with his antennae outstretched and intently 
watching the female while at work. The males are also probably 
polygamous. 
The industry of the female is well shown by the number of gashes 
made (Fig. 229 «, 6), some of which did not, however, contain any eggs. 
In the space of a square inch there were three gashes, while in the region 
where they were thickest forty were couuted in half a square foot. Of 
course when they hatch all do not live to pass through their transforma- 
tion. Whether the woodpeckers seek for and discover the larvae 
ensconced in the bark is doubtful, and yet it would be easy for them or 
other birds to pick the grubs out of their hiding places. So far as my 
observations have gone the holes made by the woodpeckers in forest 
trees are for the purpose of getting at the iuner bark rather than for 
insects. But a careful examination of woodpeckers shot in coniferous 
forests would throw light on this subject. ---.. .- -• 
In regions where the white pine grows it is infested by the Mono- 
hammus. The spruce is also often infested, but I have not seen clear 
cases where either of those trees have been killed outright by this de- 
structive borer. But during the past summer ( 1885) I have seen on the 
islands in Casco Bay and taken out the full-grown larvae from at least 
six or seven living firs, which must have been killed by the attack 
