94 Natural History Society of ]SF. Bulletin No. IV. 
in deeper water they attain much larger size, for at L’Etaiig harbor 
they may be dredged in six or seven fathoms of water, attached to 
shells of scallops or to stones, and as large as the largest walnut. 
They vary much in external form, as indeed do all shells fixed to any 
solid body, for they must conform to the irregularities of its surface. 
Among the Radiates the Echnoderms are well represented in the 
Bay. The Holothnroids or sea-cucumbers are mostly of Ispecues, 
the large brown Bendacta frondosa and the elongated nearly trans- 
parent Synapta tenuis., both of which are abundant at the lowest 
tides upon Craig’s Ledges, a great rugged rock mass about four miles 
from St. Andrews. The common Sea Urchin {2'oxopneustes dro- 
hachiensis) lines the shore in many places with a dark green carpet 
of projecting spines, but is most abundant where there is a mode- 
rately strong tide-way or current. In many places they may be seen 
to occupy cavities in the rock, which they fit exactly and which are 
said to be made by themselves. As these cavities are only found 
where the tides are strong, it is probable that they are only made for 
the purpose of keeping the occupants from being swept away, while 
the constantly flowing tide brings to them a bountiful supply of food. 
The “Cake Urchin” or “Sand Dollar” {Echinarachnius parma) 
abounds in Chamcook harbor and at Hospital Island, at which latter 
place great numbers of the dead shells are thrown up upon the beach, 
together with those of the Hen-clam and Razor-fish. 
Of the Asteroids or Star-fishes several sj^ecies occur. The large 
red Aster acanthion ruhens and the small green A. littoralis are com- 
mon everywhere, while the ten-rayed Solaster endeoa and the “ Sun 
Star” {^Grossaster papposa) are found on the reefs around Pendle- 
ton’s Island. At Friar’s Cove the Basket-fish {Astrophyton Agassizii) 
occurs, from whose central disc five arms radiate, which soon divide 
into two equal branches, which themselves divide, and so on. In one 
case the continuous bifurcation was traced so far that 81,920 arms 
were shown to exist, and more beyond that could not be traced. 
Among the Ophiuroids tlie graceful, handsomely spotted OphiophoUs 
hellis may be found in abundance in dark pools and under rocks, and 
the drab colored, slow moving Ophioylypha Sarsii may be dredged 
almost anywhere in about ten fathoms. 
The Acalephs are represented by comparatively few species, far 
the most common being the so-called “Sun-fish” (Aurelia flavidula) 
of which great numbers may be seen floating in the waters of the 
Bay during the latter part of July and August. 
