THK FUCACE^. OF JAPAN. 57 



of equal or double the length of the vesicle. They are found 

 at the lower portions of the fertile ra mules, often assuming the 

 position of branchlets. The shape of the vesicles is an impor- 

 tant point in distinguishing practically the variety from the type. 

 It must be kept in mind, ho^Yever, that an intermediate form 

 is sometimes met with. 



Receptacles are cylindrical, simple or often divided, verru- 

 culose on the surface, and with a short stipe. They are race- 

 mosely disposed on a fertile ramule. A linear-lanceolate subulate 

 leaflet is found at the l):ise of a lower receptacle, but is usually 

 wanting in the upper ones. 



Remark on the affinity and the synonymy. The type and the 

 variety are so closed related that it is often hard to distinguish 

 them by mere description. In general aspect, however, they are 

 always quite different from each other and one never fails to 

 separate them at a glance although he will often meet with plants 

 of an intermediate character. 



A plant bearing the name Sargassum piluliferum Ag. is 

 distributed in Collins, Holden and Setchell's Phyc. Bor.-Amer. 

 No. 537, and also in Farlow, Anderson and Eaton's Alg. Exsic. 

 Amer. Bor. No. 102. On comparing it with our specimens I 

 do not hesitate to say that the American plant and our own 

 belong to different species, or at least different varieties. The 

 diagnosis of Sargassum pihdiferian given by J. Agardh in his 

 former works accords very well with our plants: but the descrip- 

 tion of the same species in his Spec. Sarg. Austr. relates much 

 more closely to the American plant than to ours. 



The present species was first reported from Japan as collected 

 by TiLESirs and described by Turner in 1808. The specimen 

 seems to have been incomplete and the specific definition was 



