216 THE BOTANICAL MAGAZINE. [Vol. xxxv. no. 4in. 



the cytological structures and the presence of the zoospore and 

 antherozoid in the former favour the view that the resemblance bet- 

 ween them is superficial, and not fundamental, i.e. it is due to an 

 accidental parallelism ; perhaps this view will be certified when the 

 study on the colouring matter of Colcocheete is completed. 



In the course of the study Bang-in fusco-purpurea has often been 

 examined in connection with Porphyra. The nucleus, chroraatophore 

 and pyrenoid are quite identical with those of Porphyra, though its 

 nuclear division has not yet been observed. 



Thus, it will not be unreasonable to assume that the cytological 

 details of Porphyra so far as studied, as described in the previous 

 paragraphs, are the prevailing characters in Bangiales. Bangiales is 

 said to have a close affinity with Prasiola, which is hitherto classified 

 as one of the ChlorophycccE (9, 10). But I am inclined if it will not 

 be more reasonable to put it in Bangiales. Discussion on this point I 

 hope will be given in a future paper.* The gap which now separates 

 Bangiales from Chlorophyceas is so wide and deejj that a connecting 

 link is not easily to be found. 



Prof. K. Okamura was early in opinion that Porphyra has a 

 close affinity on the one hand with Cyanophyceaj having a connecting 

 link in Porphyridium cruentiim and with Prasiola on the other, by 

 the similarity of chroraatophore and structure of the frond, though 

 he did not publish his opinion in any periodicals. My conclusion 

 agrees well with his opinion. 



The conclusion therefore may be safely drawn from details stated 

 above that Bangiales has descended from some plant or plants of 

 Cyanophycete on the one hand and from Prasiloa on the other, and 

 Floridae from Bangiales ; in other words, Cyanophycea and Floridae 

 are connected by Bangiales. In short, the evidences strongly favour 

 the view that Rhodophycea; S])rung from a Cyanophycean stock 

 rather than from Chlorophycean one and that Floridae descended 

 throiigh Bangiales, which may reasonably be called Protoflorida- as 

 proposed by Borgesen. The prevailing characters in this line are a 



*After the nianuscript was finished, I found a paper on Prasiola done by Stechell 

 and Gabdneb (Phycological contribution I. T^niv. Calif, public. Botany. 7. 1920J. in 



which they state " but the resemblance between them (Prasiola) and the species 



of Porphyra, as well as the resemblances in cell structure, particularly as regard tlic 

 shape and position of the chromatophore, suggests strongly the possibility of a nearer 



relation to the Bangiales thnn to the IHvales and a remote (?) " Their opinion 



strongly favours my view. 



