Fresh-Water Algce, of Canada. 453 



of this plant seems to arise, not from the extended cilise at the 

 extremities of the filaments, as we find to be the case in B. bom- 

 businum and others, but from the clear, and apparently lubricous 



TIL 



Fig. 2. B. moniliforme. Whorls and fibrillce, magnified. 



sbeath, in which the filaments are enclosed. This sheath we 

 have not represented in the figure (3): its appearance is'so clear and 

 delicate that we despaired of expressing it in a wood-cut. Under 

 the microscope it has the appearance of a line of light surround- 

 ing and uniting the cells, so that they do not come into contact 

 with one another, as they appear in the figure, but are separated 

 by this mucous integument. These cells contain a light-green 

 endochrome, in which there are distinct and dark colored granules. 

 The probability is that these granules are zoospores, which, on 

 the maturity of the plant, break through the cells, and, be- 

 coming fixed, germinate like the mother plant. The proper 

 fructification is however by glomerules, which grow in the 

 whorls, and seemingly spring like buds from the articulations. 

 They are in this specimen composed of three or four cells, much 

 enlarged and swollen at the extremities, and very club-shaped.. 

 The two upper articulations emit numerous articulate branches, 

 which radiate in all directions, and vary in length. This is 

 a most distinct and curious object. It is surrounded with 

 a, very thin coat of mucous, and contains bright green granules. 

 We are unable to say how it germinates. Whether it is a bud 



