791 



the ordinal division of Cryptogamia into such groups as Algae, Lichens 

 or Fungi. In alluding to the term orders, so applied to them, he 

 pun gently remarks, " we should rather call them disorders" This 

 remark is followed by a subdivision of the Algae into three subclasses, 

 which we give in extenso below, and to which we invite the reader's 

 earnest attention ; and he will see that colour is made the leading dis- 

 tinction, and he will find this leading distinction scarcely, if at all, 

 supported by the structural details subsequently given. Far be it 

 from us to assert that we possess the clew to a better arrangement ; 

 but we do unhesitatingly express our conviction, that the division of 

 these tribes will hereafter be made to rest on structural differences ; 

 and that colour, if it chance to mark such structurally distinguished 

 groups, will be held rather as a subsidiary than a primary character. 

 It will be a curious, interesting and highly valuable discovery, should 

 it be found that colour is even tolerably uniform throughout a class 

 or order of animals or vegetables ; but we are of opinion this remains 

 to be proven. 



" 1. Melanospermea. Plants of an olive-green or olive-brown 

 colour. Fructification monoecious or dioecious. 1. Spores olive-co- 

 loured, either external, or contained singly or in groups in proper 

 conceptacles ; each pore enveloped in a pellucid skin (perispore), 

 simple or finally separating into 2, 4, or 8 sporules. 2. Antheridia, 

 or transparent cells filled with orange-coloured, vivacious corpuscles, 

 moving by means of vibratile cilia. Marine. 



" 2. Rhodospermete. Plants rosy-red or purple, rarely brown-red 

 or greenish-red. Fructification of two kinds, dioecious, always formed 

 on separate individuals. 1 . Spores [gemmules, Ag.) contained either 

 in external or immersed conceptacles, or densely aggregated together 

 and dispersed in masses throughout the substance of the frond. 2. 

 Spores (called tetraspores, gemmules, Thw.) red or purple, either ex- 

 ternal or immersed in the frond, rarely contained in proper concep- 

 tacles ; each spore enveloped in a pellucid skin {perispore), and at 

 maturity separating into four sporules. Antheridia (not observed in 

 all) filled with yellow corpuscles. Marine, with one or two excep- 

 tions. 



a 3. Chlorospermece. Plants green, rarely a livid purple. Fruc- 

 tification dispersed through all parts of the frond, the whole colour- 

 ing matter being capable of conversion into propagula. 1. Spores 

 (sporidia, Ag.) green or purple, formed within the cells, often (always?) 

 at maturity vivacious, moving by means of vibratile cilia. 2. Gem- 

 mules (coniocystcB, Ag.) or external vesicles containing a dense, dark- 



