— 20 — 



Cylindrocarpus rugosa Okam. 



Nonii Jap. ； Shiwa-no-kciw ひ. 

 ： PL. V, Figs. 1-6. 



Cylindrocarpus rugosa Okam. Alg. Jap. Exsic. (日 本 海藻 標品) 

 Fas に II, No. 88 ； Id. Contents of the Alg. Jap. Exsic. II (Bot. Ma^ 

 Tokyo, Vol. XVII， 1903) p. 131 ； 日本 藻類 名彙 p. 123. 



ronds, when solitary, form more or less circularly expanded, 

 leather-like crust which attains the size of from a few cm. to 10 or more 

 in diam.， and afterward become confluent. The thickness of crust, wnich 

 measures 0.5- 1.5 mm., decreases as it proceeds from the centre to- 

 ward the periphery. Frond when young firmly adheres to sub- 

 stratum with its whole under-sarface by emitting abundant hair-like roots, 

 and in its young sta^e, it has even and flat upper surface ； but as it 

 advances in a^e, it becomes more and more wrinkled and folded, and 

 the most part of central portion of frond becomes detached from the 

 substratum. Assimilatory filaments are long, linear, fastigiate and slightly 

 torulose. Unilocular sporangia are elongated oval or oblong, and are 

 furnished laterally with a one or two-celled short filiform pedicel. 



Hab. : On rocks at and above high tide-mark. Common along 

 the Pacific coast. Snima, Idzu, Suruga, Saga mi, Boshyu ； Hakodate. 

 — Sporangia in late spring. 



A distinct species, distinguished from the typical plant, C, Berkeleyi . 

 (Grev.) Cr. by its non-hemispherical and wrinkled crust-like frond. 



PL. V， Figs. 丄 -6. Fig. 1: solitary frond in nat. state and size. ― 



rig. 2 : vertical^ section of frond, showing wrinkled surface, slightly 



magd. ― r 1^. 3， portion of vertical section of frond, ma^d. ― Fig. 4 : 



-assimilatory filaments, a hair and sporangia, one of which is full of 



