diagonal course in entering the bark, before assuming the tjf\ 
longitudinal direction, and though usually, do not always, lie clo! 
the wood. Though much smaller in diameter than those of S. destru 
they are nearly as long, and I have seen one four inches in length. 
number of eggs laid in a burrow is about a hundred; they are depofi 
behind a continuous layer of frass, which does not encroach on ei 
the floor or roof. The period of oviposition is about a week later 1, 
that of 8. destructor. I have several times found a male and a feit 
beetle in the burrow when it was less than half-an-inch long, and be! 
any eggs had been laid, but never after that period. The larva f 
their hybernacula in the thickness of the bark, hardly ever in the w 
S. multistriatus is a much less hardy insect than S. destructor, aud o 
the species of Scolytus I had in captivity last winter, multistriatx 
the only species of which I failed to rear even a single specin 
Moreover, I have observed that in a state of nature, but a comp; 
tively small proportion arrive at maturity, which to some extent accoi 
for its rarity. I have never observed any indication of autum' 
specimens. 
4. Scolytus peuni, Ratz. I have met with this species (usun 
considered a rare one) in apple and pear trees, and have found its ah 
doned burrows in apricot. It is said to affect various fruit trees. '. 
apple tree in which I have found it had been slowly dying, success^ 
strips of the bark from top to bottom of the tree had died year al 
year, and it was in the last strip that .S'. pruni had burrowed and cc 
pleted the death of the tree ; I have met with traces of its having m. 
sparingly attacked the previous strips. 
Unlike the other species of the genus which make nearly uniforr 
cylindrical burrows (there is often a trace of a diverticulum near 1 
entrance of 8. destructor'^ burrow), the first part of the burrow oft 
pruni is a nearly square chamber, as if two burrows had for so far be 
placed side by side. I have found the male beetle in this cavity in bi 
rows little more than begun, and in others nearly two inches long, a. 
have no doubt that it is formed by the male beetle, who eats the res'erv 
material as food : iu none of the other species have I found the m« 
•residing in the burrow for more than a very brief period. 
The remainder of the burrow is from two to four inches long, a; 
slightly encroaches on the wood. The eggs are covered by a layer r 
fine frass, which usually forms merely a series of detached patches fiUii. 
up the egg cavities to the level of the wall of the gallery. The Ian 
almost invariably bury themselves in the wood for hybernation, and tJ 
