127 



Callymenia cribrosa Ilarv. 



Norn, Jap. : Tsufcasa-ami, 

 PL LXXXVI. 



Callymenia cribrosa Ilarv. in Transact. Ir. Acad. 1 r ol. 22, p. 

 555 : Id. Phyc. Austr. t. 73 ; J. Ag. Epicr. p. 219 ; Dickie in Journ. 

 Linn. Soc. Dot., \ T ol. XV, 1876, p. 451 ; DC Toni Phyc. jap. nov. 

 1895, p. 26; Id. Syll Alg. IV, p. 295. 



Frond gelatinoso-membranaceous, attaching to other algae or 

 corals with minute scutate discs which are mostly formed near the 

 base of frond or at any parts where the plant comes in contact with 

 foreign bodies. Thus, the plant becomes, when fully grown, very 

 much undulato-plaited and somewhat umbilicated, and it attains 30-60 

 cm. both in length and breadth with an irregularly roundish outline' 

 but scarcely two specimens of the same shape. Margin is quite 

 entire, and wavy, and usually from casual laceration the outline 

 becomes more lobed. At all ages the frond is pierced with holes ; 

 but they vary in dimensions according to the age, either of the speci- 

 mens, or of portions of them. In the very young frond, and in the 

 expanding margins the holes are minute ; gradually they increase in 

 size until they attain 3 cm. in diameter, and always preserve a tolerab- 

 ly regular circular or oblong outline. When the holes are very 

 densely set the interstices between them are narrow-linear and the 

 network resembling that of Ulva reticnlata is formed, but when they 

 are scattered the interstices are very broad and perforations are 

 irregular. Cystocarps are minute, dot-like, dark-red, and sunk in the 

 substance of the frond, through which they are scattered. The fila" 

 ments of the medullary region are rather laxly interwoven. The 

 colour when quite fresh is a deep crimison-lake, from which it passes 



PL. LXXXVI XC : June, 1912. 



