Wood.] 334 [April. 



of its parent. This continues to grow in length, without increasing 

 very greatly in diameter, and, without obtaining any endochrome, 

 gives origin to a new cell of still less calibre than itself by the same 

 process of pullulation, which is repeated again and again, until 

 finally a number of cells are produced, severally of less diameter than 

 the preceding, none of which contain endochrome. In this way a 

 filament is formed, which gradually tapers to a long slender point and 

 is ended by a very narrow cell, apparently consisting simply of a 

 primordial utricle. Reproduction in this plant takes place both by 

 zoospores and resting spores. In the formation of the former only a 

 single cell is concerned. The whole endochrome of such a cell con- 

 tracts itself into a mass of a more or less globular shape. When the 

 zoospore is sufl&ciently developed to enter upon its independent ex- 

 istence, an opening for its exit is obtained at the distal end of its 

 parent cell by the separation of the two cells, in a sort of hinge-like 

 manner, they remaining attached at one corner. No ciliary motion 

 takes place before the exit of the zoospore, but the latter is coated 

 by a thick gelatinous layer, and the motion during its passage from 

 the cell is so slow as to be scarcely perceptible. In a little while 

 this gelatinous coat dissolves off, the zoospore begins to exhibit a 

 rocking motion, oscillates more rapidly, and finally darts off on its 

 career. 



According to Mr. Henfrey, some of these zoospores develop into 

 the ordinary filament, whilst others on germinating produce only 

 male plants; of this I cannot speak, as I have never seen a zoospore 

 develop. When a resting spore is about to be formed, two cells join 

 themselves, the proximal cell of the two emptying its endochrome into 

 the other, through an opening in the wall, which becomes very much 

 swollen and crowded with the contents of the two, and finally assumes 

 in our species a somewhat globular form, with its contents gathered 

 into a dense protoplasmic ball, not filling the case. Whilst this has 

 been going on in our species, the male filaments appear, generally on 

 the 'emptied cell; at first this is composed of a single cell, but in a 

 little while a second distal one is formed, and finally spermatozoids 

 appear in the latter; never that I have seen more than two being 

 formed in the species vinder consideration. The spermatozoids differ 

 from the zoospores, in that they are much smaller and are not colored 

 green. At this time an opening takes place in our species, in the 

 proximal portion of the sporangium, through which it is said the 

 impregnation takes place by the entrance of the spermatozoids. I 

 have watched the latter swimming around the orifice, but have never 



