1903.] ON THE VEGETATIVE MULTIPLICATION. 5 



This alga has a thick fleshy frond which branches somewhat in an 

 irregularly alternate manner on all sides. Stem and branches are cylindrical 

 or sometimes compressed and ramuli are somewhat clavate. They are 

 obtuse at apex, tapering toward their bases. Kamuli arise here and there 

 in aggregation from sides and axils of branches. On their apices knobs are 

 developed afterwards. 



Of the structure of frond, we find, first of all, the central axis whose 

 growing apex slightly stretches out beyond a groove on the top of branches. 

 Mode of growth of shoot is monopodial and the apical cell is articulated by 

 horizontal partitions. Deciduous hair-leaves are developed in spiral iusertiou 

 from the articulations beneath the apical cell. Surrounding the axis, there 

 are five pericentral cells from which gradually shorter and roundish cells 

 arise by repeated branching, so as to form a thick inner layer of frond 

 that is finally covered by a single layer of cortical cells. So-called basal 

 cell of hair-leaves is produced from every axial cell, and as its branches7 it 

 gives rise, as I have already mentioned above, to axes of knpbs and the 

 remaining ordinary branches. Frond is more or less loosely constructed 

 within in younger branches, while the older portions are more solid. In 

 loosely formed parts, so-called hyphal cells traverse through the interspaces. 

 Tetra.sporangia are developed in number in not much altered fertile ramuli 

 either standing lateral or axilal. They are formed, as it is usual for the 

 plants of Eliodomelaceae, as an upper accessory cell of a pericentral cell. 

 The latter does not form directly two large " Deck-Zellen," as it is the 

 case in the related algae, but, by branching twice or thrice, it passes to 

 cortical cells which are similar in size and appearance as the remaining 

 ones. 



Judging from such anatomical characters, one will not hesitate to 

 admit the plant in question as a species of Chondria. The conclusion 

 which J. Agardh has drawn from his study with the original specimen, 

 then, must be due to its not-good preparation, as he expresses '' Specimina 



hujus originalia, liaitd optime prceparata, examinavi, '' Indeed, 



Chondria crassicaicUs Harv. is to be ranked, 'in my opinion, among the 

 tribe Ch. Macrocarpae. 



Botanical Laboratory, 



Imperial Fisheries Institute, Tokyo. 



10, Dec, 1902. 



