t62 botanical gazette [march 



granules 



observed close to the nucleus. There is a time previous to the differ- 

 entiation of the zoospore when the nucleus lies close to the cleavage 



finaU) 



Close 



surface 



granules which migrate 



shaped arrangemeu 

 plast is established. 



granule 



results, exceDtinsr Strasburger 



:onium 



in the interior of the cytoplasm (Cycas, Ginkgo, Zamia 

 Marsilia, Gymnogramme, OnocleaT" sometimes from a ] 



Hydrodictyon, Polytoma, Der- 

 besia), and in still another case from The interior of' the nucleus 



nucleus (Adiantum, ^pidium 



(Marchantia). 



In Nephrodium, as has Just been described, the mitoses which occur 

 within the antheridium were all investigated, from the first sperma- 

 togenous cell until the final differentiation of the spermatid. The 

 blepharoplasts were demonstrated by the differentiation of stains as 

 two small deeply staining bodies appearing first within the c}i:oplasm 

 of the spermatid mother cell. The nucleus of the spermatid mother 

 cell is in the resting condition when these bodies appear, and durir 

 the mitosis which differentiates the spermatid the blepharoplasts are 

 situated near the pole of the spindle. After the telophase one bleph- 

 aroplast accompanies each daughter nucleus and there is estab- 

 lished a spermatid with a single blepharoplast. Sometimes blepharo- 



appeared in spermatogenous 



antheridium 

 spermatogen 



-Us do not represent 



formation 



spermatid mother cells; on the contrary, they are in this case real 

 spermatid mother cells, the number of sperms produced in the anther- 

 idium then being only eight. 



The relationship of the blepharoplast and the centrosome.—The 

 centrosome in pteridophvtes was figured first by Humphrey (il) and 



Caikins (39) in the spore mother cells of such forms as 



Osmunda, ?&ilotum, Adiantum, and Pteris. One year after Calkins 



ppeared, Sel\w^ account (80) of IVIarsilia and Onoclea w^as 



