ALGJE OR SEA-WEEDS. 155 



(1.) Mclanospermcce, which are marine plants of an olive green, 

 or olive brown colour, having a monoecious or dioecious fructifica- 

 tion. The spores are olive-colored, each enveloped in a pellucid 

 skin, and either simple or separating into two, four, or eight 

 sporules. They produce antlieridia, or transparent orange-colored 

 vivacious corpuscules, moving by means of vibratile cilia. 



(2.) Rliodospermea. which with one or two exceptions, are 

 marine plants, mostly of a rosy red or purple colour. The fruc- 

 tification is of two kinds ; either of spores in external or immersed 

 conceptacles, or densely aggregated together and dispersed 

 throughout masses of the frond ; or of tetraspores of a red or 

 purple colour, external or immersed in the frond, and each en- 

 veloped in a pellucid skin which at maturity separates into four 

 sporules. Some possesss antheridia which are filled with yellow 

 corpuscules. 



(3.) Chlorospcrmca*, which are marine or fresh water plants of 

 a green colour. The fructification is diffused through all parts of 

 the frond. The sporules are green, formed within the cells and 

 often at maturity having vibratile cilia. They produce also gem- 

 mules or external vesicles, which contain a dense, dark-coloured 

 granular mass, which finally separates from the frond. 



The division of sea- weeds into the brown, red, and green series, 

 is certainly a very natural one, but in the examination of dried 

 specimens, too much importance must not be attached to mere 

 colour, for although some of the red series retain their colour for 

 years, there are others which become green, olive, and even black 

 in drying ! Hence arises the necessity of paying great attention 

 to the fructification, for as my learned friend Dr. F. Mueller re- 

 marked on another occasion, " It is equally true in Botany as in 

 Divinity, that By their fruits ye shall know them." Amongst 

 the red scries, JBaUia and Ilaloplcgma assume a yellowish green 

 and tawny colour in drying, whilst Tliysanodadia becomes dark 

 reddish brown, and looks like a plant of the brown series. The 

 same may be said of Lenormandia, J\Ielantlialia, and Polypliacuin, 

 all of which, in certain conditions, may be referred by the inat- 

 tentive observer to the Melanosperme<T. There are other 

 Australian sea- weeds that change their colour in a similar man- 

 ner, but I have preferred instancing those species of which I have 

 specimens in my possession. "With respect to the fructification 



