throughout the year, and there are at least two generations per 
year as far north as the Lake States. Eggs are laid in circum- 
ferential galleries in branches from 1% to 4 inches in diameter 
and the larvae tunnel away from the gallery, following the grain 
of the wood. When the adults emerge, they fly to the tops of the 
trees and feed on the buds, in twig crotches, in the axils of leaves, 
and in immature acorns. Because of these habits and because of 
the abundance of the species in oak-wilted stands, this species is 
strongly suspected of playing a primary role in the transmission 
of oak wilt disease (116). 
Other common eastern species of Pseudopityophthorus are as 
follows: (1) P. pruinosus (Eichh.)—breeds primarily in dead 
and dying oaks; also in beech, blue beech, hickory, maple, and 
hop hornbeam. Smooth-barked branches in the upper parts of 
standing trees are preferred, but slash and other recently felled 
material also are attacked. The adult is dark brown and about 
1.8 to 2 mm. long. This species is also under suspicion as a pos- 
sible vector of the oak wilt fungus (615). (2) P. pubescens Black- 
man—breeds in various oaks, American hornbeam, and chestnut 
in the Southeast. The adult is dark brown and about 1.8 mm. long. 
(8) P. asperulus (LeC.)—breeds in various species of oaks, 
chestnut, and gray birch from Maine to Florida and Texas. The 
adult is dark reddish-brown and from 1 to 1.5 mm. long. 
The genus Conophthorus Hopk. contains a number of species 
which have the unique habit of breeding in the cones of conifers. 
The adults are small, stout, dark brown to black, and about 1.25 
to 4 mm. long. The female adult bores into a cone at the base and 
then up through the axis, constructing a small tunnel and deposit- 
ing eggs at intervals in small niches along its sides. The larvae 
feed on the scales, seeds, and tissues of the cone, often completely 
honeycombing the interior. Infested cones wither and die before 
reaching maturity. 
The white-pine cone beetle, Conophthorus coniperda (Schwarz), 
occurs throughout most of the natural range of its host, white 
pine, in eastern America. The adult is shiny-black, from 2.8 to 
4.2 mm. long, and covered with moderately long, erect hairs. 
Winter is spent in the adult stage in infested cones on the 
ground. These adults begin to emerge in late April and fly to the 
tops of nearby pines. When a female finds a suitable cone, she 
bores into it and across the axis. Then she turns and bores along 
the axis. Males join her at this time and the tunnel is extended 
the full length of the cone (fig. 94). The larvae feed on the seed 
and tissues until full-grown and then pupate in cells at the ends 
of the tunnels. Infested cones die and fall to the ground in a few 
weeks. Some adults emerge during the fall but the majority do 
not emerge until the following spring. Some of the fall-emerging 
individuals fly to the tops of pines and attack first-year conelets ; 
the remainder stay on the ground where they attack other in- 
fested cones. There is one generation per year. 
This is one of the most destructive insect pests of white pine 
seed. During certain years entire seed crops in many stands in 
New England are completely destroyed (572). Most of the dam- 
age results from the killing of second-year cones; however, con- 
256 
