No. 449.] 



STUDIES ON THE PLANT CELL. 



385 



Structure. It is probably the morphological expression of a 

 dynamic center in the ^gg. Coenocentra have been known for 

 several years and have been given especial attention in the 

 recent investigations of Stevens, '99 and '01, and the author 

 (Davis, : 03). They will be further considered in our account of 

 Coenogametes (Section III). 



Nematoplasts are exceedingly small rod or thread like 



Fig. 3. — Cytoplasmic structures, a, Coenocentra of Saprolegnia ; i, oogonium, each 

 egg origin with a coenocentrum; z, coenocentrum and nucleus from mature egg. 

 b, Nematoplasts from hair of Momordica. i. , Nucleus from apical cell of Sphacela- 

 ria, aster with centrosome. d, Nucleus from oogonium of Fucus, aster with centro- 

 sphere. e, Nucleus from germinating spore of Pellia, centrospheres with short 

 cytoplasmic radiations faster like), y, Nucleus from procambium cell of Vicia, kino- 

 plasmic caps, g, Pollen mother-cell of Lilium, filarplasm in form of multipolar 

 spindle, h, Development of sperm of Gymnogramme ; i, blepharoplast at side of 

 sperm nucleus ; 2, blepharoplast elongating and developing cilia; 3, mature sperm, 

 blepharoplast and nucleus in parallel bands, cytoplasmic vescicle below. After 

 Zimmermann, Hof, and Belajeff. 



Structures reported by Zimmermann ('93, p. 215) in the cells of 

 hairs of Momordica and the root of Vicia (see Fig. 3B). It is 

 probable that organs described by Swingle, '98, and Lagerheim, 

 '99, under the names of vibrioides are the same as or closely 



