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YAMPOLSKY : INHERITANCE OF SEX-RATIOS IN MERCURIALIS 73 



sexes but a definite point between the extremes of femaleness and 

 maleness. He gets females which show feathered antennae of 

 medium size (feathered antennae are a male character), but which 

 are otherwise normal in appearance except that they produce 

 fewer eggs which are fertilized normally. He gets females which 

 have gone a step further towards maleness in the appearance 

 of male wing pigmentation and so on progressively until a female 

 becomes a male. With the increasing tendency towards maleness 

 there is a loss in the power of the female to lay eggs and examina- 

 tion reveals the transition of ovaries into testes. 



In his male cultures he has secured stages in transition beginning 

 with a pure male up to a 75 percent female, while in his female 

 cultures he has secured what he calls "female males," which can 

 be regarded as the limit of the male extreme. Goldschmidt 

 proposes the term "intersexes" for these individuals. Any one 

 of the above individuals, Goldschmidt claims, can be secured at 

 will by crossing certain strains. 



The striking parallelism in the behavior of Goldschmidt's 

 cultures of females and my cultures of females in Merciirialis 

 annua is significant. Potentially Goldschmidt's female "inter- 

 sexes" may be regarded as functional. It is merely a matter of 

 environment that prevents their functioning. The females of 

 Mercurialis are self-fertile and produce seed. The female plant 

 that produces one seed on self-fertilization is more a female than 

 the one that produces 230 seeds upon self-fertilization. The female 

 cultures of Mercurialis annua may be regarded as exhibiting transi- 

 tion stages from femaleness towards maleness. 



Correns's work on gynodioecious plants is interesting in the above 

 connection. Plantago lanceolata exhibits various gradations in 

 forms between the hermaphrodite and female. Correns finds\ 

 that the stronger the female tendency is present in a female plant 

 the weaker will be the influence of the hermaphrodite upon that 

 plant when they are crossed. The offspring resulting from his 

 cross will be females in over 90 percent of the plants. If, how- 

 ever, the female plant used tends in the direction of the herma- 

 phrodite, that is to say, it produces a few anthers, the hermaphro- 

 dite will influence the offspring so that there will be a dimunition 

 in the number of females and an increase in the number of herma- 

 phrodites. 



