110 REPORT OF COMMISSIONER OF FSIH AND FISHERIES. [404] 
The Alcyonidium ramosum (Plate XXXIV, fig. 257) is one of the most 
conspicuous species, and is often very abundant, attached to rocks in 
‘shallow water. In such situations we have often found arborescently 
branched specimens, twelve to fifteen inches high, with smooth, cylin- 
drical branches about a third of an inch in diameter. 
The Alcyonidium hispidum (p. 312) does not appear to have been 
recorded as from our coast, by previous writers, but it is one of our most 
common species, and may almost always be found incrusting the stems 
of Fucus at low-water mark, as well as the under surfaces of rocks ; below 
low-water mark it is less abundant, generally incrusting Phyllophora, 
and other stout, palmate alga. It is easily distinguished by the slender, 
acute, reddish spines, of horn-like texture, which surround each of the 
cells. It forms soft crusts of moderate thickness, gradually extending 
over the surface of the sea-weeds to which it becomes attached. 
The A. hirsutum has also been hitherto overlooked on our coast, but 
is common, living under the same circumstances as the last, and some- 
times associated with it, both above and below low-water mark. I have 
found it in the greatest abundance in some of the large, rocky tide-pools 
on the outermost of the Thimble Islands, east of New Haven. It was 
there growing chiefly upon Phyllophora membranifolia, in some cases en- 
tirely covering and concealing the plant, from the base of the stem to the 
tips of the fronds. It also often grows on the “ Irish moss,” Chondrus 
crispus, on rocky bottoms in shallow water. It forms rather thin, soft 
crusts, which have small, soft papille scattered over the surface; from 
the summit of each of these papilla zodid protrudes, when they ex- 
pand, and displays an elegant little wreath of tentacles, much as in 
A. ramosum, (see fig. 257.) The A. parasiticum is also a species hitherto 
neglected on our coasts. It forms thin crusts on alge and hydroids, 
which generally become coated with a layer of fine sand or dirt. I 
have not observed it at low-water, but have found it at the depth of a 
few fathoms on rocky bottoms in Vineyard Sound. 
The Vesicularia dichotoma V. is a very common species, both on 
rocky shores, in pools and on the under side of stones; and in shallow 
water on rocky and shelly bottoms. It is also capable of living in 
brackish water, and is frequent on the oyster-beds. It usually forms 
cespitose clusters of many crowded, slender, white stems, each of 
which is repeatedly forked, branching in a somewhat arborescent man- 
ner. There is a little crowded cluster of small, dark-colored, oval or 
pear-shaped cells just below each fork, the cells being sessile and 
arranged in two somewhat spiral rows in each cluster. It generally 
grows about an inch high, but sometimes two or three inches. When 
expanded each of the zodids protrudes from its cell-like body a delicate 
wreath of eight slender tentacles. 
The Vesicularia cuscuta is a delicate, creeping species, which resem- 
bles, in miniature, the “ dodder-plant,” (Cuscuta,) and creeps over other 
bryozoa and hbydroids, very much as the dodder creeps. over other 
