12 



BULLETIN" 254, TJ. S. DEPARTMENT OF AGRICULTURE. 



ment, lived for several weeks after oviposition. The females which 

 overwinter copulate in the fall and may not oviposit until the follow- 

 ing spring. The time between copulation and oviposition during 

 other seasons is much shorter, generally about 10 days. As to the 

 manner of oviposition Mr. Wildermuth noted the following: "Her 

 ovipositor was already inserted when found, and she remained so 

 for 22 minutes, being first observed at 1.55 p. m. and withdrawing 

 the same at 2.17 p. m. The angle was changed several times, how- 

 ever, as she inserted the eggs, 7 in all, through the same slit which 

 was about 1 mm. in length. Of course there is no way of knowing 

 how long she had been in the position when found." Females do 

 not necessarily choose protected parts of a plant for oviposition. In 

 all cases noted with grains and grasses the egg pockets were con- 

 structed under the epidermis of the upper or inner side of the leaf. 

 Mr. George G. Ainslie noted in Florida that egg pockets in corn are 

 usually to be found in the midribs of leaves and frequently in stalks. 

 In one instance he found an egg slit in a stalk just below the tassel. 

 Eggs within the pocket are placed in a close-fitting row, with their 

 long axes parallel. The number of eggs deposited by a female 

 varies somewhat, but in general it may be said that a single female 

 is capable of depositing between 40 and 50 eggs. The number to a 

 pocket also varies from 2 to 12, with an average of 5, as shown in 

 Table VI. 



Table VI. — Oviposition of the sharp-headed grain leaf hopper in various plants. 



Plant. 



Wheat 



Barley 



Oats 



Alfalfa 



Johnson grass 



Total number 

 of egg pockets. 



22 

 16 

 26 

 16 

 2 



Total number 

 of eggs. 



102 

 85 



155 

 94 

 12 



Average num- 

 ber of eggs in 

 a pocket. 1 



4.6 

 5.3 



6 



5.8 



6 



1 General average 5.5. 



From 18 egg pockets in corn leaves Mr. Ainslie found that the number 

 of eggs per pocket varied from 4 to 20, with an average of 12. This 

 is probably due to the fact that the epidermal tissue of corn leaves is 

 more flexible, thus allowing the construction of larger egg pockets. 

 The period of oviposition may extend over from one to three weeks. 

 Oftentimes a female will construct three or four pockets in one leaf. 

 There seems to be no preference between the different grams for ovi- 

 position; however, grains and other broad-leaved grasses, such as 

 Johnson grass, are preferred to alfalfa. 



