Tricotyls, Hcini-tricotyh, and fcfracotyls. 359 



same culture. In doing su we find that they do not tend 

 to reproduce their own type, but beliave, as a rule, in the 

 same wav as tricotvls. Minor (luantitative differences 

 may occur, but of qualitative there are none. At any 

 rate it seems impossible to isolate and fix these two sub- 

 sidiary types and obtain pure hemi-tricotylous or tricotyl- 

 ous races. 



I propose to deal first with the hemitricotyls. 1 ha\e 

 repeatedly isolated them and tested their hereditary capa- 

 city, especially in Auiaraiitiis spcciosiis and Cajuiabis 

 satiz'o. In Ainaraiitus, if we plant out some hemi-t'ricotyls 

 and some tricotyls, the highest values are sometimes ob- 

 tained for the former, and sometimes for the latter ; l)ut 

 only with slight differences. For instance, in the harvest 

 of 1892 the value of 20,000 seedlings was a mean of 2% 

 for the former, and 3.5% for the latter. Moreover 

 there were slightly more hemi-tricot}'ls than tricotyls 

 amongst the former, the difference, however, was only 

 0.1% in 10,000 seedlings of each group, and in this 

 figure the various degrees of cleavage were, moreover, 

 lumped together. In 1892 to 1895 I then grew the 

 hemi-tricotyls and the tricotyls separately for tliree fur- 

 ther generations, always selecting the individuals with the 

 highest hereditary capacities. In these four years the 

 highest values obtained varied for the hemi-tricotyls from 

 4.2 to 8.5% with a mean of 5.5%, and for the tricotyls 

 from 3.6% to 7.4% with a mean of 5.7%. From these 

 figures it seems to make practically no difference whether 

 hemi-tricotyls or tricotyls are selected as seed-parents. 

 Of Cannabis satira I had in the summer of 1894 a bed 

 of each of the two types. The hemi-tricotyls gave values 

 varying from 1 to 26%, and the tricotyls from 4 to 14% ; 

 with means therefore of 1 1 and 9%. In Pcnstcnion 



