284 II. MARSHALL WARD. 



The zoosporangium (fig. 15) differs somewhat in shape from 

 that of A. polyandra, the apex especially being more pointed. 

 In a specimen carefully watched for some hours, the sporan- 

 gium was at first filled with very finely granular grey proto- 

 plasm, and two or three large vacuoles remained below, abutting 

 on the somewhat swollen-looking septum ; the tube below the 

 septum contained many and large vacuoles, the nets or bridles 

 between winch were slowly streaming. Such being the condi- 

 tion of affairs at 9.30, the only observed difference at 9.50 was 

 that the vacuoles had disappeared from the zoosporangium, and 

 the fine-grained protoplasm reached close up to the now more 

 sharply-marked septum. About 10 o'clock the tip of the spo- 

 range appeared brighter and marked by faint longitudinal striaj 

 (fig. 15 c), and a slight tendency to the formation of brighter 

 areolae seemed evident in the protoplasm. At 10.10 this was 

 distinctly marked (fig. 15 d) ; the protoplasm arranged itself 

 slowly into polygonal masses, each with a brighter central part. 

 This stage lasted for nearly ten minutes, the division lines be- 

 coming brighter and sharper, until the blocks stood nearly iso- 

 lated, and then, quite suddenly, at 10.20, the separation lines 

 disappeared and the blocks fused together, and a uniform grey, 

 granular mass (e) resulted as before. This particular sporange 

 was not observed further, but in fig. 16 are drawings of what 

 was seen in another specimen from the same cultivation. At 

 10.35 the breaking up into the preliminary blocks was nearly 

 complete (a, fig. 16) and very distinct; the hard, sharp division 

 lines disappeared quite suddenly about two to three minutes 

 later, and then the evenly granular protoplasm became marked 

 out into bright areas (fig. 16 h) by small \acuole-like points. 

 These increased slowly in size, and at 10.45 the sporange pre- 

 sented a peculiar lustrous aspect, the granules appearing re- 

 markably sharp and black in the bright, watery-looking matrix. 

 It seemed also that there were relatively more vacuoles than 

 preliminary divisions : this difficult point could not be decided. 

 At 10.50 the second series of division planes were established 

 (fig. 16 c). I could not satisfy myself that each vacuole 

 occupied the centre of one of tlie blocks, though such was un- 



