is much more strongly developed than in others, the branches in 

 them being singularly rope-like ; while in an opposite variety the 

 tips of the filaments and their lateral divisions are so nearly free 

 that the plant assumes quite a feathery aspect. 



On different parts of the coast this species differs much in size. 

 It appears to flourish best in the north, especially in muddy, land- 

 locked bays. Some specimens gathered by Dr. Greville in Staffa 

 and Iona , and figured hi that author's admirable Crypt. Flora, are 

 exceedingly luxuriant ; and I possess others from Carrickfergus 

 of nearly equal beauty. The colour, too, is subject to much 

 variation, but this is probably dependent on age, becoming more 

 and more rusty as the season advances. 



E. tomeniosus was among the earliest of the genus noticed by 

 botanists. It is described in the Historia Muscorum of Dillenius, 

 and rudely figured at Tab. 3. f. 13. of that great work. Such at 

 least is the opinion of Dillwyn : but Agardh refers the descrip- 

 tion and figure to his E. contractus, a plant which, to judge by 

 the specimens which I have seen, is only an old and matted 

 state of E. littoralis. 



Fig. Ectocarpus tomentosus : — of the natural size. 2. A small part of the 

 fibrous frond ; — magnified. 3. Portion of a filament : highly magnified. 



