Plate XII. 



Figs, 1-7. SargafiSiiDi tortile Ac. 



1. A sterile branch in the basal region of a well developed frond; 

 with cross section of llie stem. 



2. A young principal branch. In this sort of branches the leaves 

 are not refractive. 



8. Basal part of a fnll-grown plant, showing the copious ramifica- 

 tion ; each branch is cut oif near at its insertion point. 



4. Lower portion of a frond collected at Hamajima, Prov. of 

 ►Shima. This form answers to that which was mentioned by 

 KUTiîiNG under the name Halochloa padiycarpa. With cross 

 section of the stem. 



5. a. A fertile lateral branch in the upper portion of a matured 

 frond ; not a single leaf is to be found on it. This sort of 

 branch, when there is no leaf on it, is often diihcult to distin- 

 guish from Sargassum serratifoliuvi. If, however, even a single 

 leaf remain attached to it as shown in fig. 56, it can be safely 

 be referred to this species. 



6. A typical fertile ramulet. 



7. Densely pinnatifid lateral branch, often found in the lower part 

 of a frond. 



Fig. 8. Sargassum tortile f. macrocarjyum (Ac;.) 



A fertile lateral branch. In the present specimen most of the 

 receptacles lack the bractlet. In others, however, each receptacle, 

 except the ultimate ones, is supplied vvith a bractlet as shown in 

 fig. 6. With cross- sections of various parts of the stems. 



Fig. 9. Sargassum ßlicinum, Harv. 

 A fertile ramulet. 



