88 THE HISTORY OF CREATIOX. 



DesmidiacecB, of which a species of Euastrum is represented 

 ill Fig." 18 as a specimen. 



e 



Fig. 18. — Euastrum rota, a single-celled Desmid, much enlarged. Tlie 

 whole of the star-shaped body of this primBeval plant has the formal value 

 of a simple cell. In its centre lies the kernel, and within this the kernel 

 corpuscle, or speck. 



It is very probable that similar primaeval plants, the 

 soft body of which, however, was not capable of being- 

 preserved in a fossil state, at one time peopled the Lau- 

 rentian prini?eval sea in gi'eat masses and varieties, and in 

 a gxeat abundance of forms, without, however, going beyond 

 the stage of individuality of a simple plastid. 



The group of Green Tangles (Chlorophyce?e), or Green 

 Algce (Chloroalgse), are the second class, and the most closely 

 alUed to the primseval gTOup. Like the majority of the 

 Archephycese, all the ClilorophycesB ai"e coloured green^ and 



