No. 597] INHERITANCE OF SEX IN THE GRAPE 561 



hermaphrodite (FH) : 2 males (FM) and (MH). The 

 male MH is an entirely new genotype but apparently can 

 exist as shown by the next cross, in which a hermaphro- 

 dite was pollinated by a male derived from this cross. 

 Fifteen hermaphrodites, no females and 14 males were 

 produced, the expected ratio being (if a male of the type 

 HM were used) 2 hermaphrodites (HF and 11 II) : 2 

 males (MH and MF). If a normal male of the constitu- 

 tion FM had been used on a hermaphrodite of the con- 

 stitution HF we should expect to have produced 1 her- 

 maphrodite (HF) : 1 female (FF) : 2 males (HM and FM). 

 No females were produced. Again we might assume that 

 the hermaphrodite used was of the constitution HH and 

 that a normal FM male was used. In this case we should 

 expect a 1 : 1 ratio of hermaphrodites and males as before, 

 but in this case all of the males would be of the new type 

 HM. It seems, therefore, that the production of this new 

 male genotype (MH) must be admitted. Further evi- 

 dence for the production of males of this type is produced 

 in the cross female (FF) X male (one generation from 

 wild) which produced 10 hermaphrodites, 3 females and 

 7 males. If the males used had been of the normal type 

 FM only females and males could have been expected, as 

 are found under wild conditions, and no hermaphrodites. 

 If a male of the type HM were used, however, the expected 

 ratio would be 1 hermaphrodite HF : 1 male FM. The 

 presence of three females, although not expected, from the 

 cross FF X HM can be readily explained, as it has already 

 been pointed out that the males "one generation from the 

 wild" are of the two genotypes FM and HM, but of one 

 phenotype, and therefore could not be distinguished at 

 the time of pollen collection. 



The cross hermaphrodite X intermediate (origin un- 

 known) which produced 6 hermaphrodites, 4 females and 

 15 males, throws some light on the genetic constitution of 

 these intermediates and incidentally upon the suppression 

 of femaleness. Observations on a number of "inter- 

 mediates" produced at the Minnesota Fruit Breeding 



