220 A MANUAL OF DANGEROUS INSECTS. 



IMPORTANT WALNUT INSECTS. 



HEMIPTERA. 

 Coccldae. 



Armored — 



Aspidiotus (Diaspidiotus) juglandis Colv^e; Spain; Juglans regia. 



Diaspis leperii Signoret; Europe; Juglans cinerea, J. regia. 

 Unarmored — 



Lccanium coryli Linaseus; Juglans nigra, J. regia. 



COLEOPTERA. 

 Cerambycldae. 



Cerambyx cerdo Linnieus; Europe; bores ia wood. (See Oak.) 



Oberea linearis Lirmseus; Europe; bores in pith of nursery stock. (See Hi.."^. 



Saperda scalaris Linnjeus; Europe; bores in wood and bark. 



Curculionidse. 



Magdalis carbonaria Linnseus; Europe; bores in trunks. (See Birch.) 

 Alcides porrectirost.ris Marshall; India; breeds in nuts of Juglans regia. 



LEPIDOPTERA. 

 Cossldse. 



Cossus cossus Linnaeus; goat moth; Europe; bores in wood. (See Willow.) 



Tortricidae. 



Laspeyresia splendana Hiibner; Europe. (See Chestnut.) 

 Laspeyresia grossana Haworth; Europe. (See Beech.) 

 Laspeyresia amplana Hiibner; Europe. (See Hazel.) 



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

 NCssLiN, O. Leitfaden der Forstinsektenkunde, 2d ed., 1913. 

 Stebbing, E. p. Indian Forest Insects, Coleoptera, 1914, 



WATERCRESS. 



{Roripa nasturtium.) 

 A hardy market crop grown in moist soil, ditches, and water courses. 

 AN IMPORTANT WATERCRESS INSECT. 

 Limnophilus fiavicornis Fabricius. 

 (Watercress Caddis Worm. Limnophilidae; Trichoptera). 



Hosts: Water cress, Lemna. 



Injury: The larvae feed on the leaves. 



Biology: The larvae are concealed in cases and live under water. The eggs are laid 

 in gelatinous masses and are sometimes retained for a while at the extremity of the 

 female's body, but are finally attached to some aquatic plant. 



Distribution: England. 



SoRAUER, P. Handbuch der Pflanzenkrankheiten, 3d ed., 1913, vol. 3, p. 236. 



WATERMELON. 



See Cucurbits. 



WHEAT; EMMER; SPELT. 



{Triticum sativum Lam. and Triticum spp. Family Graminese.) 



Wheat is grown in many parts of the world and is a standard article of commerce. 

 The principal manner in which its insect enemies may be transported is in shipments 

 of the grain, although the occasional use of straw in packing would be liable to intro- 

 duce stem-infesting insects. The greater part of the world's wheat crop is grown in 

 Europe. For full treatment of its insect pests see Grains and grasses. 



