30 Prof. H. Karsten on the Formation, 



cell are often to be seen, soon after the action of the aqueous 

 solution of iodine, precipitated upon the membranes, upon the 

 other cellular contents, and separated from the wall ot the 

 primary cell by a colourless hyaline fluid; but by-and-by the 

 gummy-looking substance diffuses itself through the whole fluid 

 intervening between those membranes. 



The colourless and non-nuclear daughter cells (vesicles) seem 

 to contain this substance, which is coloured blue by iodine, in 

 the most concentrated form ; they are always quite filled with 

 it. Both in them and in the gum-like contents of the mother 

 cell, coloured blue by iodine, we may distinguish, when chloride 

 of calcium has been employed for maceration, delicate vesicles of 

 about the size of the large starch-vesicles which occur in the 

 chlorophyll-sac. 



This existence of organized forms as the contents of endo- 

 genous cells is of great importance for the right understanding 

 of the nature of this material, which is in some degree similar 

 to cellulose ; for, were these vesicles not present (and they are 

 moreover not unfrequently to be distinguished without the pre- 

 paration above described, particularly within the colourless 

 daughter cells), we should be entitled to assr.me that the matter 

 interposed between the primary and secondary mother cells waa 

 an adherent layer, swollen up and chemically modified by the 

 corroding substances, upon the internal surface of the former or 

 on the outer surface of the latter. 



Moreover, if it were impossible to recognize the delicate mem- 

 brane of the secondary cells within the limits of the contracted 

 chlorophyll-sac &c. after the blue colour fades by the evapora- 

 tion of the iodine, the blue-coloured mucilaginous mass between 

 the chlorophyll-sac and the primary cell-membrane might be 

 regarded as the membrane of the daughter cell modified in the 

 same way, with some of the vesicles apparently adherent to the 

 chlorophyll-band intermixed with it. 



These circumstances favour the notion that these vesicles en- 

 veloped in the gummy substance, for which I propose the name 

 celluline, outside the secondary cells, are the remains of the 

 contents of the primary joint-cell. 



It is probably to the larger or smaller quantity of these con- 

 tents of the primary cell, as well as to this change in the condi- 

 tion of aggregation of the membrane of the secondary cell, that 

 we must attribute the circumstance that the latter, during the 

 action of diosmotic fluids, such as glycerine and chloride of caU 

 cium, often separates with difficulty from the membrane of the 

 primary, and appears to be glued to this as if by a tenacious 

 mucilage. 



In many stages of development, however, the membrane of 



