CLASSIFICATION AND DESCRIPTION OF COMMON INSECTS 1 55 



Black Apple Leaf -hopper (Idiocerus fitchi Van D.). — A common pest 

 in the AnnapoUs Valley but the injury is small. The eggs are laid in 

 August and hatch from May 22d to June 13th. The duration of 

 nymphal stage (5 moults) is about 50 days. 



Beet Leaf -hopper {Eutettix tenella Baker). — (Consult Bull. 66, Pt. 

 IV, U. S. Bur. Ent.; Utah Bull. 155.) This native leaf-hopper causes 

 the "curly-leaf" disease of sugar beets in the Western States and is 

 therefore responsible for much loss. Found also on A triplex, Russian 

 thistle, Sea-blite and Sarcobatus. One brood a year. 



Adult. — Small, 3^^ inch long, pale yellowish-green to white, often 

 straw-colored. June-August. Hibernates. 



Eggs.— Vale greenish-white, elongated, tapering at the end; inserted 

 in the stems or large veins of leaf; hatch in about 2 weeks. 



Nymphs.- — White at first, becoming like the adult but wingless. 

 Active. Duration 20-25 days. July-September. 



Grape Leaf -hopper {Erythroneura comes Say).— (See Bull. 215, 

 Cornell Ag. Exp. St., 1904.) This bug is a very common pest in 

 vineyards, and occasionally does considerable injury to the leaves which 

 curl and turn brown. During the summer the nymphs feed on the 

 under surface of the leaves and give them an unnatural spotted ap- 

 pearance. The adults, mature in August, also do much harm. Feeds 

 also on Virginia Creeper, Strawberry, etc. 



Adult.- — One-eighth inch long; wings and back variably marked 

 with yellow and red. Hibernates in nearby grass and wood-lands, 

 and emerges about May ist. 



Eggs. — Three-one-hundredths inch long, semi-transparent, slightly 

 curved and faintly yellow; deposited in June beneath the lower skin 

 of grape leaves; hatch in 9-14 days. 



Nymphs. — ^Light yellowish-green with lemon-yellowish stripes on 

 each side of the body; pass through 5 stages in 20-23 days; mature in 

 July-August. 



Control. — Spray thoroughly with Black Leaf 40, tobacco extract or 

 kerosene emulsion when young nymphs appear; clean culture. 



Apple Leaf-hopper {Empoasca mali Le Baron). — (Consult Bull. 

 io8. Bur. Ent., U. S. Dept. of Agriculture, and Journ. Econ. Entomology, 

 Vol. 2, p. 54; Vol. II, pp. 144-148.) Occurs also on beans, alfalfa, 

 clover, potatoes, currants and gooseberries. 



Adult. — Slender and cylindrical, 3-^ inch long; brilliant grass-green; 



