NORMAL 





I - 2 



3-4 



5-6 



f 



7-8 



II - 12 



13 - 14 



15 - 16 



7-18 



19 -20 



22 



23 - 24 



Plate 2. Capsules of normal and trisomic Daturas. — Above is the capsule of a 

 normal diploid plant. Below are those from the twelve possible types of trisomic ; the 

 numbers are those conventionally used to designate the ends of the chromosomes, 

 the capsule labelled 1-2, for instance, having three of the chromosomes whose ends 

 are known as 1 and 2. (Courtesy of A. F, Blakeslee.) 



