358 =A. B. Verrill—Distribution of Marine Animals 
od, are occupied chiefly by southern forms, or the Virginian 
fauna, the deeper channels and the central parts of Long Island 
out much change in the depth. And equently there must 
if Vuelos: dis middle of 
Stream, as shown y the occurrence of southern forms of 
pelagic animals in their waters. 
si 
which is rarely found north of Cape Cod. But in nearly 7 
other respects the littoral fauna is very similar to that of the 
Tr 
“a oy, and especially for the absence of rocks south of New 
ork. 
In Vineyard Sound and Buzzard’s Bay the water is every- 
where shallow, usually from 8 to 8 fathoms deep, and rare é 
exceeding 12 or 14 fathoms, even in mid-channel. In Vie 
yard Sound i 
species of compound ascidians, growing in large m 
One of tl which forms large hemispherical or a 
masses, made up of an tion of long slender colonies; 
‘United together at their bases and usually thickly covered 
SS ee ae eS ee 
a oe ete te > ee 
