Reproduction and Life-Cycles 



83 



safranal and glucose, and crocin, which is decomposed into gentiobiose 

 and cis- and i)77?f5-dimethylcrocetin esters. Crocin (or a related glycoside 

 of crocetin) seems to be the motility factor, active for C. eugaynetos in 

 dilutions as high as 4 x 10-^^. The action of gynotermones was duplicated 



i-?r: 



Fig. 2. 18. A-E. Forniatioii of luicrogamctes in Ovivora tlialasscmae; A, B, 

 \1000: C-E, x2690 (after Mackinnon and Ray). F. Female gametocyte of O. 

 thalassemae; x900 (after Mackinnon and Ray). G. Microgamete of I'olvox 

 aureus; xl900 (after Janet). H. Macrogamete of Volvox globator shortly after 

 entrance of the microgamete (/??); diagrammatic (after Janet). 



by picrocrocin; that of androtermones, by safranal. The gamones were 

 believed to be mixtures of the cis- and /rfl?75-crocetin esters and the in- 

 tensity of "maleness" or "femaleness" exhibited by gametes was attributed 

 to the cis-/trans- ratio in a given mixture. 



The behavior of certain American stocks of Chlatnydojnonas differs to 



