192 DR W. B. DRUMMOND ON 
resemble in form large prawns. The sealers call them 
whale-food. Whether the whales feed on them or not I do 
not know; but terns, cormorants, and great unwieldy seals. 
derive, on some parts of the coast, their chief sustenance: 
from these swimming crabs.” Of the Schizopods, a very 
interesting form is Nyctiphanes, which is about as large as 
a shrimp, and is found swimming in great numbers off our 
own coasts, usually at some distance above the bottom. It is 
a luminous form, the light coming from a number of little 
bull’s-eye lanterns which it carries with it. The Copepods. 
are small Crustacea which are exceedingly abundant, and 
which have been found off our own coasts to form an 
important part of the food of the larger larval fishes. Very 
many of the Crustacea, even of those which do not appear at 
the surface, pass through a free-swimming stage A 
common type of the Crustacean larva is the Nauplius, which 
has a rounded body, three pairs of limbs, and a median eye. 
The barnacles which often encrust the rocks so thickly pass. 
through a Nauplius stage. These Nauplii are preyed on by 
the larval fishes. 
LEchinodermata.—The curious larve of the Echinodermata 
occur in great abundance at the surface in summer. One 
of the most common forms resembles in its general 
appearance a six-legged easel. 
The Celenterata are represented by immense swarms of 
Hydromedusee, many of which are comparatively active 
swimmers, and which may be so abundant as almost to 
render the water thick for many miles. 
Protozoa.—Of the Protozoa, the true ciliate forms are not 
very abundant, but flagellate forms are numerous enough. 
Ceratium and Peridinium are abundant off our own coasts 
at all seasons of the year. The most characteristic of the 
oceanic Protozoa are the Foraminifera and Radiolaria, which 
form the food of the smaller Crustacea. These are so 
abundant that, as they die, their shells fall like a continuous 
rain to the bottom of the ocean. Large areas of the ocean 
bottom, of depths less than 2200 fathoms, are covered by the 
famous Globigerina ooze, in which shells of these Protozoa are 
so abundant that carbonate of lime forms 95 per cent. of 
the ooze. 
