82 
87. The Red Spruce Scolytus. 
Scolylus n. sp. 
Excavates two longitudinal egg galleries from a central entrance burrow and small 
lateral cavity in the livi ing bark of branches of dying and recently felled red spruce. 
Northwestern Maine and Peak’s Island, near Portland, Me. 
Exuisit: Adult and work. 
88. The Minute Spruce Bark-Beetle. 
Crypturgus atomus Lee. 
Enters the galleries of other bark-beetles, from which it excavates numerous very 
small, irregular galleries through the inner bark of dying and dead black and red 
spruce and white pine. Northwestern Maine. 
Exuipit: Adult and work. 
89. The Spruce-Destroying Beetle. 
Dendroctonus picexperda Hopk. 
Excavates long, longitudinal egg galleries froma basal entrance burrow in the 
bark, and grooving the wood of living and injured red and white spruce trees. Very 
destructive to the ‘Jargest and best timber. Northern Maine to New York and New 
Brunswick. This is the great enemy of the red and white spruce of the northeastern 
spruce region, having caused the death and loss of a vast amount of timber. For 
methods of preventing losses, see Bulletin 28, n. s., Division of Entomology, U. S. 
Department of Agriculture. 
Exursir: Adult and work. 
ENEMIES OF BARK-BEETLES. BIRDS AND INSECTS. 
PART OX CASH 232 
90. Work of woodpeckers in spruce bark, when infested with the spruce- 
destroying beetle. 
These birds are exceedingly beneficial in destroying the greatest enemy of the 
spruce. 
Exursit: Work. 
91. The Cloudy Bark-Beetle Destroyer. 
Thanasimus nubilus K1. 
The adults feed on the adults of the spruce-destroying and other bark-beetles, 
and its young or larve prey upon their developing broods. Very beneficial. The 
specimen of ‘bark shows the aioe case of the Clerid in an egg gallery of the spruce- 
destroying beetle. 
Exuisit: Adult and work. 
92. Polyporus volvatus Peck. 
A fungus growing from entrance and exit burrows of the spruce-destroying beetle 
in the bark and the spruce-timber beetle in the wood, and from those of ‘other bark 
and wood boring insects in dying and recently dead spruce trees killed by the spruce- 
destroying beetle in the Northeast and the fir-destroying Scolytus in the Northwest. 
The presence of this fungus usually indicates the destructive work of insects. 
Exaisit: Work. 
93. Parasitic Enemy of the Spruce-Destroying Beetle. 
Bracon simplex Cress 
The adult deposits eggs in the bark with the developing brood of the bark-beetle; 
the young maggot-like larve feed upon and kill the young. Very common and bene- 
ficial. Maine to West Vi irginia. Also attacks numerous “other bark- infesting insects. 
The bark specimen shows the cocoon in which the matured larva dey elops to the 
adult. 
Exuisir: Adult and work. 
