82 pringsheim's researches on chlorophyll. 



chlorophyll-bands (fig. 9). Tn all cases, too, they appear 

 preferably at the periphery of the amylutn-boilies in the 

 bands, and before starch is visible in these (figs. 15, 16, and 

 17). So universal is this that any spot where hypochlorin 

 is observed not in relation to an amylum-body may be 

 assumed to be a seat of election for one. The constancy of 

 the appearance of hypochlorin on the periphery of the amy- 

 lum-bodies, suggests a genetic connection between them, and 

 seems to indicate that hypochlorin plays an important part 

 in the nutritive function of green cells. 



An anatomical fact, hitherto unrecognised in the organisa- 

 tion oi Spirogyra, may here be noticed. The threads of proto- 

 plasm extending outwards from the central plasma mass in 

 each cell do not, as was supposed, end in the general proto- 

 plasmic lining of the cell wall, but each passes directly or by 

 its branches to the internal surface of a chlorophyll-band, 

 and there dilates in a trumpet-like manner and grasps, as it 

 were, an amylum-body (fig. 14). If, as sometimes occurs, 

 there is no amylum-body visible at the point where the thread 

 is in contact with the chlorophyll-band, the spot may be 

 considered one where such a body will subsequently appear. 

 As the amylum-bodies increase by division, the grasping 

 protoplasmic thread also divides by forking, and thus each 

 daughter amylum-body is grasped by a protoplasmic thread; 

 and, on the other hand, the protoplasmic threads may divide 

 in the first instance, and a new amylum-body is subse- 

 quently formed in the chlorophyll-band at the extremity of 

 the new protoplasmic thread. As an outcome of this mode 

 of increase, the adjacent amylum-bodies are often connected 

 bridgeways by threads of protoplasm; and as longitudinal 

 division of the chlorophyll-bands often proceeds synchron- 

 ously with the multiplication of the amylum-bodies and 

 the forking of the protoplasm threads, the amylum-bodies 

 so connected may be in different spires of the chlorophyll- 

 band. In the angles of the forks of the branching proto- 

 plasmic threads there is usually visible in strongly growing 

 Spirogyra filaments a thickening of the substance of the 

 thread in which a vesicle, perhaps a kind of amylum-body, 

 lies. There is, then, in Sp^rogyra, a direct connection 

 through the thieads between the amylum-bodies themselves, 

 and also between them and the nucleus. 



These very definite anatomical relationships render Spiro- 

 gyra a very favourable subject for future investigation of the 

 condition in which hypochlorin exists in the fresh cell when 

 unacted on by acids. It is not, indeed, difficult to observe 

 in its chlorophyll-bands before they are treated with acid. 



