334 GLOSSARY 



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 Spermatophytes. 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 tiie 

 egg to form the egg-apparatus. 204. 



