﻿BOTANICAL GAZETTE 



to be more variable than other species, such as S. gracilis and S. prae- 

 cox. Indeed, it is stated in Gray's Manual to be "very variable 

 in size and foliage." This is interesting because of the fact that 

 Oenothera gigas is also more variable, particularly in foliage, than 

 the other, non-tetraploid, mutants. The increased variation, which 

 is of a remarkable kind in 0. gigas, is probably concerned with new 

 distributions of the quadruple chromosome series in meiosis. 



right). P ^ 1 6 1Cft) 5 ^ ^ 



Another interesting feature of S. cernua, which apparently has 

 not been reported in the other species of Spiranthes, is the prevalence 

 of apogamy and polyembryony. Leavitt 3 found that an abun- 

 dance of seed is set when fertilization is excluded, and that 1-5 or 6 

 adventive embryos occur. They vary greatly in shape, from 



3 Leavitt, R. G., Polyembryony in Spiranthes cernua. Rhodora 2:227-228. 

 1900. 



, Notes on the embryology of some New England orchids. Rhodora 3:61- 



63, 202-205. pl 33- 1001. 



