334 GLOSSAEY 



Scale : a leaf without chlorophyll, and usually reduced in size. 

 161. 



Sepal : one of the floral leaves which make up the calyx. 221. 



Seta : in Bryophytes the stalk-like portion of the sporogonium. 98. 



Sexual spore : one produced by the union of gametes. 10. 



Species : plants so nearly alike that they all might have come from a 

 single parent. 287. 



Sperm : the male gamete. 16. 



Spiral : applied to an arrangement of leaves or floral parts in which 

 no two appear upon the axis at the same level ; often called alter- 

 nate. 193. 



Sporangium : the organ within which asexual spores are produced (ex- 

 cept in Bryophytes). 10. 



Spore : a cell set apart for reproduction. 9. 



Sporogonium : the leafless sporophyte of Bryophytes. 98. 



Sporophore : a special branch bearing asexual spores. 49. 



Sporophyll : a leaf set apart to produce sporangia. 145. 



Sporophyte : in alternation of generations, the generation which pro- 

 duces the asexual spores. 97. 



Stamen : the microsporophyll of Sperm atophytes. 174. 



Staminate : applied to a flower with stamens but no carpels. 218. 



Stigma : in Angiosperms that portion of the carpel (usually of the style) 

 prepared to receive pollen. 199. 



Stoma (pi. Stomata) : an epidermal organ for regulating the communi- 

 cation between green tissue and the air. 141. 



Strobilus : a cone-like cluster of sporophylls. 161. 



Style : the stalk-like prolongation from the ovary which bears the 

 stigma. 199. 



Suspensor : in heterosporous plants an organ of the sporophyte embryo 

 which places it in a more favorable position in reference to food 

 supply. 168. 



Symbiont : an organism which enters into the condition of symbio- 

 sis. 79. 



Symbiosis : usually applied to the condition in which two different 

 organisms live together in intimate and mutually helpful rela- 

 tions. 79. 



Sympetalous : applied to a flower whose petals have coalesced. 

 227. 



Syncarpous : applied' to a flower whose carpels have coalesced. 

 226. 



Synergid : in Angiosperms one of the pair of cells associated with the 

 egg to form the egg-apparatus. 204. 



