1909] CHAMBERLAIN— SPERMATOGENESIS IN DIOON 227 



mov 



or more before the sperms separate. After 



more 



into the general cavity of the tube. Occasionally, the sperms are 

 still attached to each other after they have escaped into the tube, and 

 in such cases their movements are awkward, because they naturally 

 try to move in opposite directions. When free from each other the 

 principal movement is straight ahead, with a rotation on the long 



axis. The sperms swim 



permit 



The 



asm 



the 



sperm 



At 



asmic 



may 



sperms mi 



like a twitching. How long the 



under natural conditions, one could hardly guess. When 

 is inverted in a drop of sugar solution on a slide, and is still further 

 protected by a bell jar, the movements have continued for five hours. 

 After the sperms begin to move, there is a rapid increase in the 

 turgidity of the tube, which sooner or later ruptures at or near the 



exme of the pollen grain. Most 



sperms is immedi 



ately drawn into the opening. The first sperm may escape in two or 



may 



much 



The 



rupture is often not more than 50 fi in diameter, while the average 

 s Perm is four times as broad. But however much the sperm may be 



form 



swim. 



Efforts to keep the sperms alive after their escape from the pollen 

 ^be were not very successful. In weak sugar solutions they imme- 

 diately break to pieces, almost explode. In a 10 per cent, sugar 

 solution they quickly die. Sugar was added to a 10 per cent, solution 

 Untl1 [t became, perhaps, a 12 or 15 per cent, solution, and in this the 

 sperms continued to swim for several minutes. No experiments were 

 m ade to determine whether the sperms are chemotactic or not. 



The material would have allowed a more detailed account of the 



