GRAPE INSECTS 429 



Means of control. 



The scales and their egg-masses can often be dislodged by 

 a stiff stream of water. Many of the young lice may be killed 

 in summer by thorough spraying with tobacco extract and 

 many of the over-wintering forms may be dc^stroyed by appli- 

 cations of 15 per cent kerosene enuilsion. The cottony maple 

 scale is usually periodic in its occurrence, being often nearly 

 exterminated locally l)y its ninnerous insect parasites. 



Referen(;es 



Reaumur, Mem. Hist. Inseetes, IV, pp. 62-69. 1738. 



Putnam, Proe. Davenport Aead. 11, pp. 293-346. 1879. 



Mayet, Insectes de la Vigne, pp. 30-36. 1890. 



U. S. Bur. Ent. Bull. 22, pp. 7-16. 1900. 



N. J. Agr. Exp. Sta. Kept, for 1905, pp. 591-607. 1906. 



Col. Agr. Exp. Sta. Bull. 116. 1906. 



111. Agr. Exp. Sta. Bull. 112. 1907. 



Sanders, Jour. Ec. Ent. II, pp. 433-435. 1909. 



The Grape Scale 

 Aspidiotus uvce Comstock 



This somewhat elliptical, flat, pale yellowish-brown scale 

 measures about y^ of an inch in diameter and has the exuvial 

 spot, which is pale yellow with a whitish nipple, at one side of 

 the center. It is widely distributed in the United States and 

 occurs in Europe, Brazil and the West Indies, but is rarely 

 injurious, attacking practically only the grape-vine, especially 

 the crevices of bark from the ground to the second year's growth. 

 Vines sometimes become incrusted and may die. The winter 

 is passed in a nearly full-gro\\Ti condition. The female com- 

 pletes her growth in the spring, and during May and June gives 

 birth to from 35 to 50 living young. There is but a single 

 brood annually, and the insect spreads very slowly. Lady- 



