liS 



Delesseria Middendorfii Rupr. 



Nom- Jap: Naga-konoha-nori. 

 PL. LXXXIV; PL. LXXXV, Fig. 1-7. 



Dele'sseria Middendorfii Rupr. Tange des Ochotskischen 

 Meeres 1847, p. 237, Taf. 12; J. Ag. Sp. Alg. p. 696; Id. Epicr. 

 p. 497 ; De Toni Syll. Alg. IV, p. 708 ; |ffi *t, # ^ & m p. 50. 



The present plant is so well described by Ruprecht that no 

 further detail will be needed. Only i am here to give some des- 

 criptions of the structure of frond and cystocarps. 



In the cross-section of a young leaf, we find two layers of cells' 

 the inner median and tine outer epidermal. Cells of the median layer, 

 which are cubical or rectangular, are much larger than the epidermal 

 ones. As the part grows in thickness infra-cortical cells are gradually 

 formed and the membrane becomes more or less thickened by a thick 

 cortication on the midrib portion. The central axis is not well 

 marked out in a little advanced leaf, but in the apical portion of a 

 very young leaf we ma}' clearly see the apical cell and a few axial 

 cells as it is shown in PL. LXXXY, Fig. 5 and 7, and PL. LXXXIV, 

 Fig. 8. 



I have found cystocarps on the plants having smaller obovate 

 or oblong leaves forming rosette-like clusters abundantly proliferated 

 from older fronds of the preceeding year, as shown in PL. LXXXIV, 

 Fig. 3-9, which have been obtained in April and June at Urakawa, 

 Prov. Hiclaka in Hokkaido. Urakawa is too southern locality for 

 the distribution of this species and so I am not sure that fruit-bearing 

 plant is always such as has here been described. Procarps are 

 produced in pairs on both sides of axial cells in very young leaves 



