from the Cell-contents of the Characese. 103 



Pleotia should not be added to these, but until further obser- 

 vation proves this, I must leave it under doubt. May not the 

 " spirozoids '^ also or " spermatospheres '' of Itzigsohn belong 

 to these developments ? Their being developed in Spirogyrcei 

 from globules of endochrome which become pale, lose their 

 colour, and end in becoming " greyish -white,^^ at least, gives 

 them a strong resemblance. How the germs which produce 

 these developments exist in the cells of Algse without apparently 

 affecting their vitality, or causing a suspension of their functions, 

 is difficult to conceive; but that they do so, is proved by the 

 presence at least of one kind generally, if not always, in the 

 plants of Characese after they have attained a certain size, and 

 to that we must now chiefly direct our attention. 



My first observations on this development were made on the 

 internodes of a very small species of Nitella, but latterly they 

 have been made on the internodes of a very large one ; some of 

 the oldest of which average six inches in length by one twenty- 

 fourth of an inch in breadth. Hence they were well adapted 

 generally for experiments on this Alga *. 



Let us now direct our attention to what takes place when one 

 of these, about three or four inches in length, is so suspended, 

 that about an inch of the free end may rest upon a slide of glass, 

 in a little water, while a portion of the latter also is cut off with 

 a lancet, and the rest covered with another piece of glass for 

 observation. 



1st. The aa^ial fluid rushes forth and renders the cell-wall 

 more or less flaccid. 



2nd. The mucus-layer in part comes forth, and with it also 

 portions of the green layer. 



3rd. After a short time the expelled mucus, which is appa- 

 rently separated into masses, but is nevertheless more or less 



* There are two species of Nitella in the island of Bombay, the smallest 

 of which I have already described, and the following is a description of the 

 large one, or one in question : — 



Plant long and straggling, of a deep green colour, with short branches, 

 crowded towards the top. Oldest internodes 5-6 inches long, some fluted 

 (from collapse ?) where the endochrome has disappeared and left them of 

 brown colour ; terminal internodes shortened and crowded, compara- 

 tively. Verticils consisting of five short branches, each composed of 2-3 

 long cells applied end to end, the last terminated by a spine, five minute 

 spines round each joint, and 10-12 or more round the base of each ver- 

 ticil ; long branches rising between the short branches of the verticil. 

 Organs of fructification cast together in the axil of the verticil or singly at 

 the joints of the short branches. Globule spherical, of a brownish-green 

 colour; nucule conical, at first white, then black. General characters : — 

 Great length, dark -green colour, large organs of fructification and large 

 size of plant generally. Grows in the tank of Nagaum in the island of 

 Bombay. 



