118 SEA MOSSES. 



of opposite secondary branches, and these again in 

 like manner by their branchlets. All the divisions 

 are long and the ultimate parts very fine and hair- 

 like. Indeed, a large and beautiful plant in my her- 

 barium presents an appearance not unlike that of 

 long, wavy tresses of hair. If it never received the 

 popular name of "Mermaid's hair," it is quite time 

 it was christened that. It is reported very common 

 along all our northern shores, from February to 

 November, and less common in southern waters in 

 the summer. 



Desmarestia aculeata, Lam. 



This plant is found the year around, growing at 

 low tide and in deep water. It is very common so 

 that special localities need not be named. Frond, 

 cylindrical at base, but soon flattening; in a plant a 

 foot and a half high, as thick as a sparrow's quill. 

 Branches, alternate, irregular, half forking, much flat- 

 tened, from one-twelfth to one-eighth of an inch wide 

 two or three times sub-divided. The young plants, 

 and apparently the younger parts of all the plants, 

 are clothed with opposite pencils of fine, beautiful 

 olive-green filaments, from one-sixteenth to one-half 

 an inch long. A larger plant before me, collected 

 at Marblehead, Mass., in August, has them very short ; 



