172 | THE ATLANTIC. [onap. 11. 
alonema, from which it differs chiefly in external form and 
habit, in the smaller amount of development and concentra- 
tion of the large anchoring root-spicules, and in the form of 
these spicules and of the spicules of the outer fringe. In other 
particulars, as in design and structure of the outer net-work, 
the form of the spicules which make up the structure of the 
substance of the sponge, and the form of the double grapnel of 
the sarcode, the two genera approach one another very closely. 
Among the branches of the coral there were many specimens 
of an ophiurid, apparently of an undescribed species, and there 
were found one disk and a portion of a mutilated arm of a small 
Brisinga, whose characters do not entirely correspond with those 
of either of the species hitherto defined. 
Attached to the sponge were two examples of a fine annelid 
which Dr. von Willemoes-Suhm referred to the family Ampnt 
nomip&, subfamily Euphrosynine, with many of the characters 
of the genus Huphrosyne. The body is 12 mm. long and 5 mm. 
broad, and consists of fifteen segments. The surface of the 
head is covered with a caruncle extending over the anterior seg- 
ments, and the whole surface of the body is clothed with milk- 
white two-branched setee, which radiate over each segment like 
a fan. It can not be ascertained without careful dissection— 
which has not as yet been possible—whether this is the type of 
a new genus or a Huphrosyne with very small branchie. 
Besides the species mentioned, this rich haul yielded several © 
bryozoa, one or two corals, and one or two small sponges. 
On the following day we sounded in 2220 fathoms, on the 
opposite side of the ridge. This was one of the rare cases in 
which the “Hydra” sounding-machine did not disengage its 
weights, and we consequently lost the instruments sent down 
with it—a water-bottle, two thermometers, and a pressure-gauge 
designed by Mr. Buchanan and on trial as to its efficiency. A 
series of temperatures were taken from the surface to 1500 
fathoms, at intervals of 100 fathoms: 
