HETEROMORPHOUS GENERA. 



[chap. 



Soc. 1863) that several species of Linum are 

 dimorphous, in the same manner as those of Primula ; 

 and has shown that the existence of three forms in 

 Lythrum (Figs. TJ — 80) already observed by Vaucher, 

 is to be explained in the same manner. I shall refer 

 to this case more in detail when we come to that 

 family. Nor are these by any means the only cases 

 of Heteromorphism now known. I have already 





W-i-. ^ 



Fig- 40. — Geraniutn praietise. 



mentioned that of Oxalis, and Hildebrand gives the 

 following list of genera as containing Heteromorphous 

 species, viz., Hottonia, Primula, Linum, Lythrum, 

 Pulmonaria, Cinchona, Mitchella, Plantago, Rhamnus, 

 Amsinckia, Mertensia, Leucosmia, Drymospermum, 

 Menyanthes, and Polygonum. It will be observed that 

 these genera belong to very different groups, while on 



