92 Miscellaneous. 



fragment of the siliceous skeleton of a sponge, forming a regular net- 

 work somewhat like that of Eupledetta as figured by Bowerbank, 

 but lacking the spines. 



The soundings made during the cruise seem to indicate a kind 

 of submarine terrace, on which the dredgings of the 24th and 29th 

 were made. The cast of the 25th was probably made on the edge 

 of it ; and the dredge no doubt touched bottom only for a short 

 time, after which the ship drifted off into water too deep for the 

 line attached. — Silliman's American Journal, November 1868. 



Deep-sea Dredgings in the region of the Gulf-Stream. 



By L. F. DE PoufiTALES. 



I sent you a few days ago a small pamphlet * containing some of 

 the results of the deep-sea dredgings made by me in connexion with 

 the exploration of the Gulf-stream by the Coast Survey. If you 

 think it worthy of notice in the 'Journal of Science,' I have thought 

 it would add to the interest to mention the much more complete 

 results of this year's campaign, which were the subject of a brief 

 communication I made to the late meeting of the National Academy 

 at Northampton. As the specimens have not all been determined 

 as yet, I can give here but a short outline. 



The dredgings were made outside of the Florida reef, at the 

 same time as the deep-sea soundings, in lines extending from the 

 reef to a depth of about 400 to 500 fathoms, so as to develop the 

 figure of the bottom, its formation and fauna. Six such lines were 

 sounded out and dredged over, in the space comprised between 

 Sand Key and Coffin's Patches. All of them agree nearly in the 

 following particulars. From the reef to about the hundred-fathom 

 line, four or five miles off, the bottom consists chiefly of broken 

 shells, and very few corals, and is rather barren of life. A second 

 region extends from the neighbourhood of the hundred-fathom line 

 to about 300 fathoms ; the slope is very gradual, particularly 

 between 100 and 200 fathoms ; the bottom is rocky and is inhabited 

 by quite a rich fauna. The breadth of this band varies from ten 

 to twenty miles. The third region begins between 250 and 350 

 fathoms, and is the great bed of Foraminifera so widely extended 

 over the bottom of the ocean. 



The second, region is the most interesting, from the variety of 

 animals inhabiting it. The bottom rock, of which many pieces 

 were brought up, is a limestone, still in progress of formation from 

 the debris of the shells, corals, ifcc. growing and dying on its surface. 

 In this fauna the vertebrates are only represented by a very few 

 small fishes, and those not deeper than 100 fathoms. But all the 

 branches of invertebrates are represented ; I will mention the most 

 characteristic. Of the Mollusks, the most common is Terebratula 

 cubensis, mihi, and a new species of Waldheimia, both of large size. 

 Of the former, more than a thousand specimens, and several 

 hundred of the latter, were collected. Gasteropods are rarer and 

 mostly small, the largest being the Voluta junonia, which was 



* The article above noticed. 



