516 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [14] 
much as in the latter, while the spicula also resembles those of this 
group. This may represent a primitive type from which the Pennatu- 
lacea have been derived. It is only necessary to suppose that the at- 
tached base of such a form may have become bulbous and more special- 
ized, on account of the exigencies of muddy bottoms, as in the case of | 
our Aleyonium and Actinians, when it would become a true member of 
the Pennatulacea. It might, of course, be urged that it is a degraded 
form, derived from the Pennatulacea, but this is not probable. At any 
rate, it is evident that the Pennatulacea, as a group, are adapted speci- 
ally for life on the soft muddy bottoms of the deep sea, and probably 
were originally developed there from simpler attached forms of shal- 
low-water origin. 
The bulbous bases of the large Actinians are often useful to us in 
dredging, because they may inclose various small shells, &c., with the 
mud, and some of our new discoveries have been obtained only from 
this source. They are also very useful to us as bringing up the most 
perfect samples of the mud of the bottom, with precisely the same com- 
position that it had when undisturbed, for the bulb is often so nearly 
closed that none of the mud can wash out, while the contents of the 
dredge and trawl and of the sounding cup are more or less washed on 
the way up, and the finer parts may be largely lost. 
Another very large and handsome species of Actinian, first discovered 
in 1880, but one which does not descend to great depths, inhabiting 
only the warm zone, in 60 to 115 fathoms, is Urticina perdix V. (fig. 19). 
When in full expansion, it is often over a foot across, with its very nu- 
merous long, slender, translucent tentacles spread out in every direc- 
tion. The body is smooth and curiously mottled with shades of lighter 
and darker brownish, yellow, and pale flesh-color, something like the 
feathers of a partridge, to which the name alludes. It is one of the 
few deep-water species that thrives well in confinement. We have kept 
large individuals in aquaria all summer, without special care. It is 
very active, constantly changing in form, and very voracious. The 
temperature of the water in which it naturally lives is similar to 
that of the harbor at Wood’s Holl in summer, while most of the other 
species, coming from greater depths, live in and require much colder 
water than can be provided without special means of cooling. 
We often keep deep-sea species, of different groups, alive for a few 
hours or days by keeping them in water cooled down in the ice-box on 
the steamer, in cases where it is desirable to bring them ashore with 
their natural colors and appearance for descriptions and figures. But 
in most cases they never recover from the injury received by being 
drawn up through the warm upper stratum of Gulf Stream water, which 
is usually above 70 degrees, and although they sometimes remain alive 
for a day or two, they seldom show any activity, and usually die within 
afew hours. The Crustacea are nearly always quite dead when brought 
on deck, for, excepting the hermit-crabs, they are injured by the rough 
