from the Cell-contents of the Characese. 13 



iodine, and it seems equally so, that there are only these two 

 kinds of bodies in the nucule ; again^ these corpuscles very closely 

 resemble in colour, and in not becoming blue by contact with 

 iodine, the irregular bodies contained in the mucus-layer of the 

 internode, while they bear in other respects also a strong analogy 

 to them. Lastly, we now know, that a gonidial cell having one 

 of these irregular bodies for its nucleus or peripheral appendage 

 can develope a gonidium. Thus then, if the irregular bodies 

 and the corpuscles be identical, we have the germs of gonidial 

 substance and starch-globules as the contents of the nucule, the 

 latter being designed for the nourishment of the former. May 

 not the circular disk contain nutriment for the gonidia ? — while 

 the irregular bodies would seem to be identical with the green 

 disks, and are indeed, in many instances, almost undistin- 

 guishable from them, even when both are present among the 

 contents of the evacuated internode. 



Thus we see a great resemblance between the formation of 

 the gonidia and the germinating of the nucule, and in the for- 

 mation of both with that of the " resting spore " of Algae 

 generally. 



As yet, I have never seen a new plant developed from the 

 gonidium of Nitella, nor have I ever been able to identify their 

 germination with that of germinating cells, which I have fre- 

 quently seen on the surface of an internode containing the 

 gonidia; neither did Pringsheim see those germinate which 

 came from Spirogyra, in which he has carefull)^ described the 

 same kind of gonidial development as that which takes place in 

 Nitella"^. But Braun, who has followed the development of 

 gonidia in Hydrodictyon f, states, that the larger gonidia (for 

 there are two distinct sets, which he calls macrogonidia and 

 microgonidia) germinate, that is, form the young water-net, 

 while the smaller ones never do this, but unite into groups, 

 forming a homogeneous green mass, which becomes covered 

 with a distinct cell-membrane. This very much resembles the 

 fungoid growth at the ruptures of and about the internode which 

 follows the disappearance of the gonidia of Nitella, and which I 

 have suggested might be the last eiforts to form and to increase 

 of the remnants of gonidial substance left in the gonidial cell 

 and about the internode. Be this as it may, the dividing up of 

 a body formed after the manner of a resting spore into smaller 

 ones, resembling gonidia, which afterwards germinate, is the 



* " On the Germination of Resting Spores and one form of Moving 

 Spores in Spirogyra." Ann. and Mag. of Nat. Hist. vol. xi. p. 210, 1853. 



t Pub. of Ray Society, Botan. and Phys. Mem., Phaenom. of Rejuve- 

 nescence in Nature. Transl. ])y Henfrey, p. 261. 



