Ulvacea.'] CALOTHRix. 331 



Hab. Eocks and stones in the sea, between tide-marks. 

 Annual. Summer and autumn. 



Tliis is a most beautiful and truly elegant plant. The 

 fronds are linear-lanceolate, attenuated at each extremity, 

 and curled and waved at the margin. It is very graceful 

 in its native element, and scarcely less so in the herbarium, 

 when well prepared. The shadings produced by the plaiting 

 of the curled margin in drying add much to the beauty of 

 the plant. In early summer it is of a rich lively green, with 

 a fine gloss, adhering well to paper. In the end of summer 

 the green has become darker, and it is still glossy, but does 

 not adhere well to paper. The substance is thin,, and com- 

 posed of two closely-united membranes. It is at times 

 eighteen inches in length, and an inch in breadth. It grows 

 in clusters of more than a dozen fronds. See ' Phycologia 

 Britannica,^ PL xxxix. 



"Without following further Professor Harvey's systema- 

 tically arranged List, I shall in the ^close mention a few 

 plants that are not included in his catalogue. 



