66 A MANUAL OF DANGEROUS INSECTS. 



Ips typographus I^iaaaeus. 

 (Eight- toothed large spruce barkbeetle or "typographer." Ipidse; Coleoptera.) 



Hosts: Spruce; rarely larch and Scotch fir (Pinus silvestris.) 



Injury: Bores in bark and sapwood; while usually secondary, it also attacks 

 healthy trees when very numerous. Recognized as the most dangerous bark -beetle 

 in Europe. 



Description: Beetle black or brown, cylindrical, 4.5-5.5 mm. long, 8 teeth on mar- 

 gins of elytral declivity, of which the 3d on each side is the largest and with rounded 

 apex. 



Evidence of infestation: Shows only when the tree begins to react by changing 

 color of foliage. 



Distribution: Lapland to Alps, wherever spruce grows. 



NtJssLiN, O. Leitfaden der Forstinsektenkunde. 1913, pp. 269-272, fig. 238. 

 JuDEicH, J. F., und NiTSCHE, H. Lehrbuch der Mitteleuropaischen Forstinsekten- 

 kunde. I, pp. 506-516, figs. 167-169, 1895. 



>tcToinlcus (Myelophllus) piniperda LinnDeus. 



(The large or black pine pith borer or "forest gardener." Scolytidse; Coleoptera.) 



Hosts: Pine. 



Injury: Tunnels under bark of trunk and branches. Young adults feed on pith of 



1 to 2-year old shoots. Attack sickly and quite healthy trees and invariably cause 



their death from above downward. Attacks thin, smooth bark of trunk and branches 



and heavy barked portion of lower trunk of living felled or sickly trees. 

 Description: Beetle elongate, 3.5-4.5 mm. long; proboscis finely and not densely 



punctate; elytra finely punctate-striate, posteriorly with a row of brush-bearing small 



tubercles. 

 Evidence of infestation: Fading and dying tops; long vertical galleries in bark. 



Twigs hollow at tip with pitch tubes at base. 

 Distribution: Europe. 



NxJssLiN, 0. Leitfaden der Forstinsektenkunde. 1913, pp. 243-246, figs. 207-210. 



JuDEiCH, J. F., und NiTSCHE, H. Lehrbuch der Mitteleuropaischen Forstinsekten- 

 kunde. pp. 462-472, figs. 145 and 146, 1895. 



Bupalus plniarius Linnseus. 



(Pine Geometrid. Geometridse; Lepidoptera.) 



Hosts: Pine, spruce, fir. 



Injury: Feeds on foliage and young shoots. 



Description and biology: Male moth bright yellow, female bright reddish brown, 

 both marked with dark brown. Larva green, with three white dorsal lines and two 

 yellow lateral lines. 



Distribution: Europe. 

 SoRAUER, p. Handbuch der Pflanzenkrankheiten, 3d ed., 1913, vol. 3, p. 337. 

 NiJssLiN, Otto. Leitfaden der Forstinsektenkunde 2d ed., 1913, pp. 385-390, figs. 



315-317. 



Dasychlra selenitlca Esp. 



(Larch Tussock Moth. Lymantriidae; Lepidoptera.) 



Hosts: Larch, pine, sainfoin, herbs, hardwoods. 

 Injury: Defoliator, especially injurious to young trees. 



Description and biology: Moth brown; male olive brown; female l^rownish black, with 

 white crescent and Avavy line on wings. Larva black, with dark -gray hairs on black 



