38 Notes on the Morphology of the Fticacece. 



SARCOPHYCUS POTATORUM KUTZ. 



THE earliest record of this plant is a description and figure of 

 Fucus potatorum in 1806 by Labillardiere,* who assigned to it the specific 

 name potatorum in consequence of having observed the natives of the woods 

 round Van Diemen's Land use portions of its great fronds, folded in the 

 form of a pouch, for the purpose of keeping fresh water. Dawson Turner-f- 

 alse describes it, and gives a figure of the whole plant drawn from a 

 specimen in the Herbarium of the Jardin des Plantes at Paris. The next 

 record is that of Lamouroux,t who, in 1813, mentions this plant under 

 the name Laminaria potatornin. The genus Sarcophycus was subsequently 

 founded for its reception by Kiitzing. He was, however, under a 

 misapprehension as to the nature of the oogonia, since he regarded these 

 as tetrasporangia, and, believing the plant to be one of the Floridece 

 placed it in the order Chatangiea. Its systematic position was, 

 however, clearly recognised by Hooker, for in his Flora Australica, 

 p. 456, after describing Durvillcea Harveyi, he mentions this plant under 

 the name Laurinaria potatorum, and observes that it probably belongs to 

 the genus Durvillcea. Lastly, Areschoug,|| in 1847, gives a description 

 of the plant under its name of Sarcophycus potatorum. 



The genus founded, as has been noted, as the result of a misapprehension, 

 has been retained, for, although the genera Sarcophycus and Durvillcea 

 are very closely allied, they differ in the fact that, while the frond of 

 Sarcophycus is solid to the centre, that of Durvillcea is, beneath the 

 cortex, lacunar in structure, the lacunae being separated by strands of 

 anastomosing filaments. I am indebted to Mr. Bracebridge Wilson 

 of Geelong, Australia, for collecting the material on which I have 

 worked. 



The mature plant of Sarcophycus potatorum consists of a disk, a stipe, 

 and a frond portion. From the flat and more or less circular disk there 

 rises a stipe, which is cylindrical below and flattened above. The stipe bears 

 a huge segmented frond, the segments of which are of tough, leatherlike 

 consistency, and reach an enormous length and considerable thickness. 



A section through the frond shows that it is composed of a cortical 



* PL Nov. Holt., ii., p. 112. 



t Fuci, vol. iii., tab. 242. 



J Ann. Mus. d'Htst. A T at., xx. 



Phyc. Gen., p. 392. 



|| Ofuersigt of Kongl. Vetensk.-Akad. Forhandl. Stockholm, 1847, p. 267. 



