136 



THE AMERICAN NATURALIST 



[Vol. LIII 



The five next Fo KK females placed with Paratettix 

 males produced 1, 2, 8, 9 and 22 offspring, respectively, 

 all KK females. The sixth female of this group, ex- 

 posed to no male whatsoever, behaved precisely as did 

 those individuals which had been with Paratettix males. 

 Another of these Fo KK females was placed with an 

 MT male with 4 KK female offspring resulting in 

 F,, none evidencino- any M or T part in the par- 

 entage. Three of these were bred further and gave off- 

 spring in F^ as follows: one, without any male, 2 KK 

 females ; the second, mated to an MM male, 3 KM females 

 showing the male parentage unmistakably ; and the third, 

 mated to a YY male, 1 KY female showing male par- 

 entage clearly, and 3 KK females indicating none of the 

 male characteristics and plainly parthenogenetic. On 

 account of the extremely small numbers involved, I sug- 

 gest there is no special significance to the absence of 

 males in the two last described matings. An eighth Fg 

 KK female, of this group, was mated to an OY male and 

 gave KO 11$$: 21?? and KY 13 $5:26??. 



The following two matings show EE males mated to 

 KM females and giving KE 27JJ:26$?, ME 215$:35$$ 

 and the crossovers KME 1J:1$. Three of the KM 

 females were placed with Paratettix males, but the off- 

 spring exhibited no more evidence of male parentage 

 than those produced by the two KM sisters without ex- 

 posure to any male. The combined result from the five 

 KM sisters was AA 1:KK 26:MM 38:KMKM 1, all fe- 

 males, except that the sex of the AA individual was not 

 determined. As in the case of the KY females already 

 noted, this furnishes a very interesting exhibition of 

 segregation as well as crossing-over in parthenogenetic 

 individuals. 



Subsequently from KK females, individually and in 

 groups, but not exjioscd to males of niiv kind at anv time, 

 thcr.. l.avr 1).., ,1 ulvrii 2J2(; frinalc and 4 niah' otT>|.ring, 

 all KKs. snnu. m' Wu^m liavln- arrive.! at thr lifth par- 

 thenogenetic generation. Including the KK females rep- 



