1907] 



CA LD WELL— MIC ROC YC A S CA LOCO MA 



131 



\ 



for Cycas by Ikeno, for Ginkgo by Hirase (8), for Zamia by Webber, 

 and for Stangcria by Lang (9). The cone had lost its vigor, however, 

 and no cases of fertilization were secured. 



The full significance of this remarkable number of sperms in each 

 male gametophyte cannot be known without an investigation of the 

 origin of the body cells. No other seed-plant has been found to have 

 more than two mlile cells in each male gametophyte. The fact that 



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Fig. 9.^A relatively young plant removed from the earth. 



there are in Microcycas sixteen mother ceils, each organizing a sperm, 

 is especially suggestive when it is recalled that a common number of 

 sperms in each antheridium of the leptosporangiate ferns is thirty- 

 two. Another division of the body cells of Microcycas would result 

 in this fern condition. It will be of great interest to know whether 

 any of the four cycad genera as yet uninvestigated possess this remark- 

 able character. 



