334 I'rocccdiiuis of flic Ohio Statr .Icddcmy of Science 



lOO staminatc to 154.24 carpellatc individuals. Xoll in experi- 

 ments witli licm]) found that tlie ])ercentage of staminatc and 

 carpellatc offspring derived from the seeds of a single plant 

 varied materially from the normal ratio whatever that may be. 

 In some extreme cases only 10% were carpellatc. in others 90% 

 were carpellatc. He concluded that the egg does not determine 

 the ratio, otherwise there would not be such extreme variation. 

 Then he crossed individual carpellatc plants with pollen from a 

 single anther with the result that the ratio of the oiTspring 

 showed a very close approximation to the normal. A plant 

 crossed with pollen from a single anther produced 100 staminatc 

 to 1 17.3 carpellatc offsj)ring while a plant crossed wath pollen 

 from a single inHorescence produced 100 staminatc to 12 1.6 

 carpellatc offspring. Noll concluded from these experiments 

 that the ratio of staminatc to carpellatc plants in the offspring 

 is determined by the sperm in the pollengrain and not by the egg. 

 But I fail to see any evidence whatever for such a conclusion ; 

 even were the ratio 1:1 in the first case and 1:1.5 i'^ ^'^^^ sec- 

 ond. If the ratio is determined by the sperm, why should there 

 be any difference in behavior between ])ollen taken from one 

 anther and pollen taken from an indefinite number of anthers 

 from various individuals, when a certain per cent, of the pollen- 

 grains from each anther is supposed to contain the male de- 

 termining characters and the remainder the female? So far as 

 we know the cell changes in all the anthers is essentially the 

 same. There is nothing in fact on which to establish a case, 

 for the ratios Noll dctermincfl in his experiments are far within 

 the ratios obtained in nature by the statistical method. If the 

 difference obtained proves anything at all, which is very doubt- 

 ful, it shows merely that the sperms or eggs of some individuals 

 or some flowers are more prepotent than others. In the case 

 of the hemp, all we can say at present is that the ratio between 

 staminatc and carpellatc plants seems to be exceedingly varia- 

 ble. The sex tendency may be so evenly balanced that some 

 small external or internal factor may determine the condition. 

 Thus under a normal environment the ratio should be rather 

 constant in the numbers of carpellatc and staminatc plants. 



