72 PDCACEiE.— HiMANTHALIA. IV. 



A remarkable plant, common on the coasts of Northern Europe, where, in 

 England, it has the popular name " Sea-thongs," which is nearly a literal trans- 

 lation of the sounding Greek imposed by Lyngbye. The view here taken of the 

 frond and receptacles is that first given by Greville and Wahlenberg, and more 

 recently adopted by Agardh; and I have no doubt but that it is the correct view. 

 Dr. Greville has well observed that the pezizas-form or cup-shaped base, here called 

 the frond, attains its fall size before any portion of the strap-shaped branches con- 

 taining fruit, and here called receptacle^ makes its appearance. The branching 

 receptacle then grows with rapidity, and after it has ripened spores, falls away. 

 The plant is biennial, and, like all biennials, the first year is wholly occupied with 

 the formation of the top-shaped frond ; the receptacle is rapidly produced in the 

 second season. Late in the autumn, when the old ripe receptacles are thrown ofi' 

 and drifted ashore in large banks, the young fronds for the next season may be 

 seen sprouting in myriads round the dying ones of the last year. Carmichael says 

 that the old fronds sprout again the second season, but I have never observed them 

 do so, though I have repeatedly sought for such second growth. 



1. HiMANTHALiA lorea^ Lyngb. ; frond top-shaped, at length collapsing, plano- 

 convex, stipitate ; receptacles repeatedly dichotomous, linear, tapering to the 

 extremity. J. Ag. Sp. Alg., vol. 1, p. 196. Rarv. Phyc. Brit. t. 78. Fucus loreus, 

 Turn. Hist. t. 196. E. Bot. t. 569- Fl. Dan. t. 710. 



Hab. Rocks near low-water mark. Biennial. " Coast of North America," jide 

 J. Agardh. (v. v.) 



Fronds an inch in height, top-shaped, the centre of the disc becoming depressed, 

 and at maturity throwing out a strap-shaped receptacle from two to ten or even 

 twenty feet in length, from a quarter to half an inch in width, tapering to the apices, 

 and many times forked. Conceptacles scattered in myriads through the whole 

 length of this gigantic receptacle. 



I have seen no American specimen of this plant, and am not aware on what part 

 of the shore it has been gathered, or by whom communicated to Professor Agardh. 

 Judging from probabilities, I should suppose that it may have been found at 

 Newfoundland, or to the north of that island. It is much more abundant in 

 Europe, on the northern coasts, though said to extend southward as far as Spain. 



