[419] INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 125 
deseribed from specimens dredged by usin Vineyard Sound. It is often 
handsomely banded with light red and pale yellow. It is still a rare 
species, but has been dredged also near New Haven. 
The Ascidians, with the exception of one or two additional species 
seldom met with, are the same as those of the rocky bottoms, and they 
often occur in immense quantities, especially the massive sandy ones, 
Amarecium pellucidum, (p. 401,) and the “ sea-pork,” A. stellatum, (p. 
402,) which together often almost entirely cover the bottom over areas 
many acres in extent. They furnish excellent hiding-places in the open- 
ings and crevices between their lobes for numerous Crustacea and Anne- 
lids, many of which can be easily secured by putting the masses of 
these ascidians into buckets of water and leaving them until the water 
begins to get stale, when they will come out of their retreats in large 
numbers and seek the surface or edges of the water for oxygen. Or 
they may be pulled apart directly and the various creatures secured at 
once, ” 
The Molgula arenata (Plate XX XIII, fig. 251) is a nearly globular, 
but often somewhat flattened species, which covers itself over with closely 
adherent grains of sand or gravel. It is most common on sandy bottoms 
but is found also on gravelly ones. _ 
The Ciona tenella is an elongated, erect species, attached at base to 
rocks, dead shells, &c. It isremarkable for the transparency, whiteness, 
and softness of its integument, and for the bright orange ocelli around 
its orifices. It is rare in this region, but very common in the Bay of 
Fundy.. 
The Bryozoa are very abundant, especially on the shelly bottoms. 
Some of them grow on alg, hydroids, ascidians, &c.; and many 
form inecrustations on the dead shells and pebbles. The two most 
abundant and prominent species are Bugula turrita (p. 311, Plate 
XXXIV, figs. 258, 259) and Escharella variabilis, (p. 312, Plate XX XIII, 
fig. 256.) The former grows attached to the various sea-weeds in great 
quantities, forming delicate white plumes, often six inches to a foot in 
length. The latter mostly forms calcareous incrustations over the sur- 
faces of dead shells and pebbles, thin at first, but eventually becoming 
thickened by the formation of layer over layer, until the crust may be- 
come half an inch to an inch in thickness, with a tabulated and vesicu- 
lar structure in the interior. The masses thus formed often closely 
resemble genuine corals, especially some of the ancient fossil forms, 
and they often occur in great quantities. When living the color is dull 
red, but when recently dried they have a yellowish-green color, which 
easily bleaches out, however, by exposure to the sun and air. Vesicu- 
laria dichotoma, (p.404,) Alcyonidium ramosum, (p. 404, Plate XXXIV, 
fig. 257,) and Crisia eburnea (p. 311, Plate XXXIV, figs. 260,261) are 
usually abundant. Most of the remaining species have also been men- 
tioned in the previous pages as inhabitants of rocky bottoms, or else 
among the shore species. 
Among the species not previously mentioned are Cellepora scabra, 
