THE FIICACE.E OF JAl'AX. 117 



in tlie apical jnirt of a more or less broadened leaf. When fully 

 formed they become more spherical than those of /. typica and 

 are frequently inermous. The receptacles are cylindrical, more 

 or less narrowed above and have a short filiform stipe. 



At an early stage of development, this forma is hardly sei)a- 

 rable from /. tijpica. But as soon as the fronds have reached 

 half a foot in height, the characteristic broad fulcrant leaves 

 serve unmistakably to distinguish it from the others. In a full 

 grown individual the frond attains 3-4 feet in total height. The 

 lateral members are much further apart than in /. typica and 

 their avera2;e lens-th is less than an inch. The stems of the 

 principal branches are 2-onim. thick, and are five-ridged. A 

 ridge is generated downwards from each insertion point of the 

 leaves which are disposed spirally upwards in a screw -wise 

 direction. 



Forma nippomca also is not easily separable from /. typica 

 while it is yet young. When it has attained to about a foot in 

 total height, the lateral branches elongate to a considerable degree, 

 often exceeding the principal branches in length. The ramulets 

 on the lateral branches are quite stunted and approximate. The 

 leaves on the ramulets are almost all transformed into small apicu- 

 lated vesicles. The richness of the vesicles in the lateral branches 

 is an important point in the practical distinction of this forma 

 from /. typica. Receptacles are found at the terminal 23oint of 

 the stunted ramulet, and are usually solitary. 



This forma is most abundant on the Japan Sea side from 

 Nagasaki as far as Saghalin. On the coast of the Pacific side 

 it seems to be confined to the vicinity of the eastern entrance 

 of the Tsugaru Strait. 



Remark on the systematic position. It can be easily demonstrated 



