June 10. 1918 



Nysius ericae 



573 



eggs. Usually several trials are made before the female is satisfied and 

 deposits the eggs, and sometimes the attempt is discontinued, to be re- 

 sumed shortly afterwards. 



Females have been observed to remain occupied at oviposition for 

 as long as g}4 minutes, and as many as eight eggs have been found 

 where a single female has been at work. 



INCUBATION 



Early in the incubation period a red spot appears near one end of the 

 ei^g and at about the middle of the period two spots appear near the 

 other end. The egg remains a translucent pink, and with proper magni- 

 fication the developing nymph is plainly visible through the trans- 

 parent shell. 



NYMPHAL INSTARS 



In conducting these experiments, after many unsuccessful attempts 

 to rear the nymphs by ordinary laboratory methods, the newly-hatched 

 nymphs were placed singly in bags of thin muslin or India Hnen which 

 were slipped over the tips of growing plants and tied securely. This 

 method proved more nearly successful than any other which was tried, 

 though the handling necessary during examinations resulted in consid- 

 erable loss through accidental injury to the nymphs or to their escape. 

 At Garden City, Kans., in 191 4, five individuals were held under close 

 observation from hatching until death. At Wichita, Kans., in 191 6, 

 three individuals, one of which was kept until its death, were reared to 

 maturity from eggs of known oviposition. The number which reached 

 maturity, however, represents only about X of i per cent of the indi- 

 viduals used in the rearing experiments. 



NUMBER AND LENGTH OP INSTARS 



In Table I are given the number and length of instars obtained from 

 five nymphs reared at Garden City in 19 14. 



Table I. — Number and length of nymphal instars of Nysius ericae, Garden City, Kans., 



1914 



Specimen No. 



Sex. 



I . 



4- 

 29 



33 



35 



Male. 



Do. 

 Female. 

 Male. 



Do. 



