HANDBOOK OF SEA- WE EDS. 21 



They are deep sea plants, or at least grow about low water 

 mark. The largest of the group is Desmarestia ligulata, 

 which, with the other British species, D. aculeata, is often cast 

 ashore. The latter species, at an early period of its existence, is 



Fig. 12. Fucus serratus, showing a transverse section of the Conceptacle, 

 and Antheridium with Antherozoids escaping. 



clothed with tufts of slender hairs, springing from the margin of 

 the frond. Desmarestia viridis is the most delicate and also the 

 rarest of the three. Nothing like fruit has been discovered on 

 any of them. Arthocladia villosa and Sporochnus pedunculatus 



