I30 



BOTANICAL GAZETTE 



[august 



ally the downward growing branch of the tube in which the mass 

 of sperms is found is thin-walled, as are the ascending and lateral 

 branches {'fig, 28). By dissecting pollen tubes from a cone that had 



Fig. 8. — ^An 



been kept in the laboratory for two months, motile sperms were 

 observed; the general form is shown in fig. jo. So far as could be 

 determined, their behavior was similar to that of the sperm described 



