NOTES ON RECENT RESEARCH. 



275 



These bodies increase in size, are surrounded by a membrane, and become 

 vacuolated ; their kinoplasmic radiations take no part in spindle forma- 

 tion ; they eventually break up into numerous granules. The cilia-bear- 

 ing band of the spermatozoid is formed from the blepharoplast. The 

 entire spermatid cell becomes a spermatozoid. The above-mentioned 

 band is a helicoid spiral of five or six turns. The pollen tubes appear to 

 produce part of the fluid in which the spermatozoids swim. 



The mature spermatozoids are very large, being visible to the naked 

 eye. The cytoplasm of the spermatozoid unites with that of the egg-cell, 

 and their nuclei also unite. 



The paper is of great interest to students of the nucleus, cytology, and 

 centrosomes. The figures are exceedingly good ; there is also a biblio- 

 graphy. — G. F. S.-E. 



