212 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [506] 



E ADI AT A. 



Ecliinoderms. 



Page. p a o- e . 



tStereoderma uniseinita 503 Asterias vulgaris 496 



t*Echinarachnius parrna 503 I *Cribrella sanguinolenta. .. 407 



Strongylocentrotus Drobach- 



Ophiopholis aculeata 496 



iensis 406 



Acalephs. 



Page. 



*Platypyxis cylindrica 408 



*Clytia Johnston! 408 



Eudendrinm ramosum . . 408 



Page. 



*Plumularia, sp 407 



Hydractinia polyelina. .... 328 



Polyps. 



Page. I Page. 



Edwardsia lineata 497 | Alcyonium carneuin 497 



PROTOZOA. 



Sponges. 

 Page, j Page. 



Chalina oculata 497 



Polymastia (?) 497 



fMassive siliceous sponge . . 503 



IV. 5. FAUNA OF THE MUDDY BOTTOMS OFF THE OPEN COAST. 



Within the depths to which our dredgings extended, very few true 

 muddy bottoms occur. The deposits of mud on the open coast usually 

 begin to occur only at the depths of twenty -five to thirty fathoms, and 

 even at these depths there is a considerable admixture with fine siliceous 

 sand. The central and deeper portion of the depression in line with the 

 axis of Vineyard Sound is, however, occupied off to the west of Gay 

 Head and No Man s Land by a deposit of fine, soft, sticky mud, filled 

 with the tubes of Annelids and Ainphipods, (Ampelisca, &c.) Dredgings 

 were made on this bottom at localities 85, c, in 18 fathoms ; d, 19 fathoms ; 

 e, 11 fathoms. On September 9, the temperature at 85, c, was 58 Fah 

 renheit at the bottom, and 62 at the surface ; at d, it was 57 at the 

 bottom and 62 at the surface 5 at e, it was 59 at the bottom and 63 at 

 the surface. This muddy bottom abounded in Annelids, small Crustacea, 

 and bivalve shells. 



In several other localities, where the bottom was a mixture of mud 

 and fine sand, the mud seemed to predominate and to determine the 

 character of the life, so that such localities have been classed with the 

 muddy bottoms, though the fauna differed considerably from that of the 

 soft muddy bottoms referred to above. In the following list, however, I 

 have specially designated the species found in the typical localities of 

 each kind. 



