INSECTS OF HAWTHORN AND HAZEL. 133 



DIPTERA. 

 Trypetldae. 



Ceratitis capitata Wiedemann. (See Fruit.) 



HYMENOPTERA. 

 Ten thredln idae • 



Macrophya punctum-album Ltnnceus; Russia; sawfly. 

 Priophorus padi Linnaeus; Europe (See Plum.) 



LITERATURE. 



SoR.vuER. P. Handbuch der Pflanzenkrankheiten, 3d ed., 191.3, vol. 3. 

 LiNDiNGER, L. Die Schildlause (Coccidse), 1912 



HAZEL; FILBERT; COBNUT. 



{Corylus spp. Family Corylaceae.) 



Valuable nut-bearing shrubs or rarely trees of America, Europe, and Asia, some- 

 times used for shrubbery. 



A. HAZEL INSECTS LIKELY TO BE IMPORTED. 



Erlophyes avellanse Nalepa; Eriophyes vermiformls Nalepa. 

 (Hazelnut Blister Mites. Family Eriophyidse; Acarina.) 



Hosts: Corylus avellana, C. tubulosa. 



Injury: Cause galls on buds. Serious in England. 



Description and biology: Four-legged blister mites which form galls in the spring 

 and summer buds. Very easy to introduce on nursery stock. 



Distribution: England, Europe. 

 SoRAUER, P. Handbuch der Pflanzenkrankheiten, 1913, 3d ed., vol. 3, p. 118, 



fig. 93. 



Oberea linearis Lmnseus. 



(Cerambycidee; Coleoptera.) 



Hosts: Hazelnut, walnut. 



Description and biology: Adult, beetle occurs from May on. A generation in two 

 years. The larva eats pith and wood and pupates in earth. JEggs are placed singly 

 under young bark. After oviposition the female rings the twig. 



Distribution: Europe. 

 SoRAUER, P. Handbuch der Pflanzenkrankheiten, 1913, 3d ed., vol. 3, p. 507. 



Curcullo nucum Linnaeus (Balaninus). 



(Nut Weevil. Curculionidae; Coleoptera.) 



Hosts: Hazelnut, filbert, cob, oak. 



Injury:^ Causes nuts to fall prematurely. 



Description and biology: Adult, length 8 mm.; color tawny brown to chocolate 

 brown, densely clothed with golden-brown pubescence; has unusually long snout; 

 ^occurs in June and July (England). Flies in bright weather. Pupa creamy white, 

 pupates in soil. Larva length rather more than 8 mm.; creamy white; passes winter 

 in cell in ground. Eggs are deposited singly, deep in nut. Incubation requires 8 or 

 10 days. (See text fig. 68.) 



Distribution: Europe. 

 Theobalc, F. V. Insect Pests of Fruit, 1909, p. 299. 



