138 A MANUAL OF DANGEEOUS INSECTS. 



A. HORSE-CHESTNUT INSECT LIKELY TO BE IMPORTED. 



^~ Zeuzera pyrlna Linnseus. 

 (Horse-chestnut Borer. Cossidse; Lepidoptera.) 



Hosls: Elm, alder, ash, beech, birch, horse-chestnut, linden, maple, oak, willow, 

 poplar, buckthorn, spindle tree, mountain ash. 



Injury: Bores in bark and wood of trees. 



Description and biology: Moth white, with steel-blue round spots; wing expanse 

 50-70 mm. Larva yellowish, more flesh-colored when younger, with shining black, 

 warts; head, thoracic shields and legs black. The larva bores in the wood and pupates 

 in a cell of frass near the outside. 



Distribution: Europe, North Africa, and introduced into North America. 

 SoRAUER, P. Handbuch der Pflanzenkrankheiten, 1913, 3d ed., vol. 3, p. 321. 

 Hess, Richard. Der Forstschutz, 1900, vol. 2, pp. 84, 85. 

 NiJssLiN, Otto. Leitfaden der Forstinsektenkunde, 2d ed., 1913, pp. 321, 322, figs. 



273-275. 



B. IMPORTANT HORSE-CHESTNUT INSECTS. 



HEMIPTERA. 

 Coccldae. 



Unarmored — 



Lecanium coryli Linnasus; Europe; Aesculus hippocastanum, A. pavia. 



COLEOPTERA. 

 Anobiidae. 



XestoUum rufovillosum De Geer; Europe; bores in dead wood of standing and living trees. 



Bostrychidae. 



Sinoxylon perforans Schr.; Europe; bores in branches. 



Scarabseidse. 



Melolonthahippocastani Fahncmsajid M.melolonthaLumieus; Europe ;ilarvEe injure; roots of seedlings. 



Cerambycldae. 



Phymatodes lividus Rossi; Germany; bores in wood of felled trees and lumber. 



Ipidse. 



Anisandrus dispar Fabricius; Germany; galleries in wood. 



LEPIDOPTERA. 

 Geometridae. 



Anisopteryx xscularia Schiflermiller; Europe; feeds on foliage. ' 



LITERATURE. 



NtJssLiN, Otto. Leitfaden der Forstinsektenkunde, 2d ed., 1913. 

 SoRAUER, P. Handbuch der Pflanzenkrankheiten, 3d ed., 1913, vol. 3. 



HORSE-RADISH. 



(Radicula armor ada. Family Cruciferse.) 



An herb cultivated for its roots. 



IMPORTANT HORSE-RADISH|INSECTS. 



COLEOPTERA. 

 Chrysomelidse. 



Phyllotreta nigripes Fabricius, and P. arworacix Koch; Europe, North America. (See Crucilers.) 

 Phyllotreta atra Fabricius; Europe; flea beetle. 



LEPIDOPTERA. 

 Pyralidse. 



Pionea forficalis hinneeus; Europe. (See Cabbage.) 



