202 



Davis. 



leaved foliage similar to that of the culture as a whole. Buds and 

 flowers of all 3 plants agreed closelj' with the mass of the culture. 

 Thus in this culture, 12'13 muricata W X gigas, as in the same cross 

 grown in 1909 there were presented two groups of plants but the 

 narrow-leaved type was perfectly represented by only one individual 

 since the other two plants outgrew largely the indications of their 

 rosette stages. The presence of these two transitional or intermediate 





Fig. 22. Rosette of hybrid, 12"13 ma, muricala W X gigas. A plant with narrow leaves 



similar in form to those of muricala, compare with Figs. 4 and .5. This type of rosette 



was represented by 3 individuals in a culture of 40 plants, the mass of which presented 



broad-leaved rosettes of the form shown in Fig. 19. 



plants suggests that the tlifferences between the extremes of the culture 

 may not be of the character to be expected when distinct classes of 

 hybrids are formed. 



My last crosses between in»>7crt/a and gigas were grown in 1913, 

 the muricala parent being of the race from Holland, isolated by DE 

 Vries, and designated in my cultures as muricata H. As has before 

 been stated these cultures were set out in a bed treated witli bone 



