40 "Vol- XLin., Art. 1.— K. Yendo: 



— the part near the base of the blade in proportion to the whole 

 length, which measures 10-20 meters when the sporophylls begin 

 to appear — are transversely stretched. Remember that the young 

 and sterile frond of this species may have the blade 10-20 meters 

 in length and 20-30 cm. in breath, and when nearly matured the 

 blade is fully one meter broad. This shows that the blade, after 

 it has completed or nearly completed its growth in length, must 

 extend its breadth with an astonishing speed. More stretching in 

 the transverse direction than in the longitudinal, is naturally to 

 be expected. This is indicated by the disposition of the epidermal 

 •cells and by the transverse stretching of the glands. 



Setghell and Gardner stated in their joint work. Algae of 

 the North-western America, p. 276, that the stipe of A. fistulosa 

 "seems to be free from mucilage ducts, but the blade in both 

 forms (f. stenophylla Setch. and f. platyphylla Setch.) possesses 

 abundant structure of this kind, just under the outer layer of cells, 

 as GuiGNARD has indicated." But so far as I have examined 

 Japanese inaterial I could not find true mucilage ducts in the 

 frond of A. fistulosa. 



I will take this opportunity to say a few words on Guignard's 

 observation directly concerning this subject. He disproves the 

 presence of the " cavité mucifére " in the frond of Undaria jnn- 

 natifida Sur. {= Ulopterix pinnatifida Kjellm. = Alaria pinnatifida 

 Harv.). It will clearly be understood that the brownish spots 

 frosted all over the blade of this plant did not attract his atten- 

 tion. He mentions two species of Alaria, A. esculenta Grev. and 

 A. grandi folia J. Ag., as lacking the mucilage canals. He did not 

 examine the embryonal fronds of these species. Lastly, he points 

 out the presense of " canaux muciféres très gros et très nombreux 



