AMERICAN DREDGINGS IN THE CARIBBEAN SEA. 
361 
teresting isopod, with gigantic lateral processes on the posterior 
segment, was also obtained from 300 fathoms. Many hermit- 
crabs occupied tubes of bamboo or cavities in dead wood and 
sponges, of which they completely closed the orifice, with one 
of the large claws flattened like the operculum of a Serpula. 
Among the molluscs, the preliminary report of Mr. Dali (in 
Letter No. 2), mentions the most important types. We obtained, 
however, in addition, a good set of Pleurotomaria, one specimen 
measuring five inches in height, while another was so small 
that the slit, from which the genus takes its name, existed only 
as a slight indentation. I hope to supply Mr. Dali with the 
material necessary for an anatomy of this interesting genus. 
But by far the most interesting of the molluscs is a Spirula, 
from a depth of 950 fathoms, in excellent condition. The small 
number of Waldheimia collected this year is quite striking ; 
other species of Terebratulse were more common. We found, 
as was usual last year, an immense number of dead Pteropod 
shells at all depths, playing a most important part in determin- 
ing the nature of the deep-sea bottom. 
The collection of fishes is excellent ; its special characteristic 
is the large number of Lophioid types it contains. We also 
obtained many of the genera collected by the Challenger . 
Some of the rarer pelagic fishes, which are occasionally caught 
at sea, are undoubtedly either full-grown deep-sea fishes or their 
young. It becomes an interesting problem to know where the 
young remain, before they become permanently inhabitants of 
deep water. 
The pelagic fauna of the eastern part of the Caribbean Sea is, 
during the winter season, rather scanty. Owing to the con- 
stant agitation of the water, I had no opportunity, as in the 
Gulf, to make much use of the surface tow-net. From the 
number of fragments of Siphonophora constantly found they 
must be very numerous. In the roadstead, under the lee of 
the islands, there was but little pelagic life to be found. Every- 
thing either remains at a short distance below the surface, or is 
blown out to seaward of the islands. The phosphorescence, in 
consequence, is far less brilliant than in the Gulf of Mexico, 
although occasionally the masses of Ctenophora (a species of 
Mnemiopsis), swimming at different depths, produce a very 
striking illumination ; sudden flashes of light suddenly appear- 
ing as if coming from great balls of fire floating a short dis- 
tance below the surface. The most striking phosphorescent 
phenomena were produced by a small Annelid, allied to Syllis, 
which moved over the surface of the water with great rapidity, 
performing the most remarkable gyrations, and tracing its path, 
which remained phosphorescent for a short time, by a brilliant 
line of light. Among the deep-water forms, several of the 
