20 DEPARTMENT BULI^TIN 779. 



grain fields to underestimate the numbers of this species present, and 

 very often the resulting damage is attributed to other causes. 



HIBERNATION. 



Although large numbers of nymphs enter hibernation quarters with 

 the adults, they soon perish and in no instance have they been ob- 

 served to survive the winter. 



HABITS OF ADULTS. 

 COPULATION. 



The adults of Chlorochroa sayi are found in copulation on the food 

 plants, under rubbish, or around the bases of plants at all times of the 

 day and night. The mating pairs face in opposite directions and the 

 length of copulation varies from a few minutes to several hours. 

 In one life-history cage a pair was observed in copulation for two 

 entire days and it is probable that they had continued in this position 

 throughout the intervening night. On several occasions, when ob- 

 served in copulation on their food plant, either one or both of the 

 sexes continued to feed during the act. 



OVIPOSITION. 



Oviposition occurs at any time of the day or night whenever the 

 female happens to be resting or feeding. When ovipositing the legs 

 are strongly braced and the abdomen is inclined at an angle, nearly 

 touching the object on which the eggs are deposited. As each egg is 

 forced through the ovipositor, the tip of the abdomen bends and de- 

 posits the egg in its appointed position. Normally the eggs in the 

 lower end of a cluster are deposited first and with these as a founda- 

 tion the succeeding eggs are added in transverse rows. (See fig. 3.) 

 The intervals between the deposition of individual eggs in a cluster 

 average about one minute, so that the total time required for oviposi- 

 tion depends upon the size of the ^gg cluster. 



LOCATION OF THE EGG CLUSTERS. 



The Qgg clusters of Chlorochroa sayi are found in a great variety 

 of locations, but generally are placed on the lower side of some por- 

 tion of the food plant or underneath some object in the vicinity. 

 The adults emerging from hibernation deposit their eggs on the rub- 

 bish or dead plants comprising the hibernating quarters, but the 

 adults of the succeeding generations generally select the living food 

 plant, or its close vicinity, for egg deposition. On different occasions 

 egg clusters have been found on various parts of the food plant, in- 

 cluding the awn or " beard," the edges of the leaves, the head of 

 beardless varieties, the upper and lower sides of the leaves, and the 

 stem. Other locations selected for egg deposition were the lower side 

 of " cow chips," clods of earth, stones, and tin cans, and the wire and 

 posts of fences. On one occasion an egg cluster was found super- 



