94 CHARACE^. 



They require for their growth highly nutritious substances, 

 such as dead organic matter : this by their thalli, or thousand 

 rootlets, they quickly disorganize, appropriating a small por- 

 tion of it to their own nourishment, but allowing the return 

 to earth, to be again appropriated in some other form of tissue, 

 of by far the greater portion of those substances. 



The Charce are frequently called Stoneworts, from the 

 quantity of calcareous matter with which they are often in- 

 crusted, or perhaps which they evolve, this property rendering 

 them agents still more important in the formation of soil. 



5. NITELLA Ag. 



Char. Plant more or less pellucid. Cells tuhidar, not in- 

 vested tvith a secondary layer of smaller cells. Globules 

 and nucules mostly on the terminal whorls, and axillary. 



Of tliis and the following genus no figures are proposed 

 to be given, as their inclusion did not enter into the original 

 intention of the work. This is the less to be regretted, as very 

 good figures of the species are extant, especially those of 

 " Eng. Bot." 



1. NiTELLA TRANSLUCENS Ac/. 



Char. Stem elongated, flaccid, pellucid, glossy ; branches of 

 the ivhorls spreading, elongated. Xucules and globules 

 approximate, on the smaller ramidi scarcely hracteated. 



Chara translucens, Eng. Bot. 1855, 2d ed. t. 1467, Hook. 

 Crypt. Fl. parti, p. 245. ; Macreight, 278.; Nitella 

 translucens Ag. Syst. Alg. 124. 



This species grows in deep and stagnant ponds : it has been 

 found in several localities, but is by no means common. It 

 is the largest of our native species, and well adapted, from its 

 transparency, for microscopic examination, of which it has 

 often been made the subject. Tlie whole plant is exceedingly 

 smooth and glossy, whence its name. The distance of the 

 whorls, and thickness and size of the branches, vary in differ- 

 ent sj'jecimens. Fructification met with from July to Sep- 

 tember. 



