192 



UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



an egg had been after hatching. In others the epidermis was blackened. 

 In the case of the mortality in the eggs, already referred to, these 

 spots were very numerous ^ 



and probably interfered 

 somewhat with the normal 

 functions of the leaf, but 

 ordinarily these small punc- 

 tures have no noticeable 

 effect on the leaf. 



THE NYMPH. 



The young-, immature 

 hopper is called a nymph. 

 It differs from the adult 

 chiefly in the fact that the 

 wings are not fully de- 

 veloped. These are grad- 

 ually acquired with each of 

 the five successive molts 

 until after the last stage, 

 when the adult with fully 

 formed wings appears. The 

 stages may be easily recog- 

 nized by the development of 

 the wing pads. The relative 

 size is indicated in the pho- 

 tographs (Fig. 11), which 

 were all taken under the 

 same magnification. 



The Hatching Process. 

 Several young nymphs were 

 observed in the process of 

 emerging from the egg cov- 

 ering, and it generally re- 

 quired from ten to fifteen 

 minutes for this process. 

 After remaining quiet for 

 a few minutes just outside 

 the eggshell they would 

 move about until they found 

 a suitable ' place for insert- 

 ing their beaks for food, 

 where they would remain 



