INSECTS INJURIOUS TO BEETS AND SPINACH 



341 



nymphs appear in July and are very active, being first found in the 

 unfolding leaves at the centre and later spreading to all parts 

 of the plant. The nymphs are variously colored, but the com- 

 monest form is a pale creamy color with a brown saddle on the 

 middle of the abdomen and various mottlings on the prothorax 

 and wingpads. The nymphs become full grown in from sixteen 



FIG. 245. " Hopperette " designed for collecting leafhoppers. (After G. C. 

 Davis, Mich. Agr. Exp. Sta.) 



to twenty-two days and the adults again become abundant 

 in August and September; they evidently hibernate as adults, 

 as no more eggs are laid in the fall as far as observed. 



The characteristics of the " curly leaf " are described by Dr. 

 Ball as follows: " The first symptom of ' curly-leaf ' or ' blight ' 

 of the beet is a thickening of all the smaller veinlets of the leaf, 



