466 BULLETIN OF THE BUREAU OF FISHERIES. 
throughout the Bay and Sound (chart 251), but is most abundant off exposed situations, 
as at Gay Head and Cuttyhunk, where extensive growths are present. 
Phyllophora membranijolia is also found on stones and over sand and mud; it was 
dredged in 3 to 17 fathoms (most plentiful in 4 to ro fathoms). The species is likewise 
distributed very generally throughout the Bay and Sound (chart 252), but appears to 
prefer rather more sheltered situations than Phyllophora Brodiat. > 
Both species of Phyllophora are prominent in the cool- as well as the warm-water 
sublittoral formations. 
(46) THE AGARDHIELLA ASSOCIATION. 
Agardhiella tenera is very common on stones and shells in fairly deep water; it 
grows in 2 to 15 fathoms (most plentiful in 4 to ro fathoms). The species is very widely 
distributed throughout both the Bay and Sound (chart 253), but prefers rather sheltered 
waters and is a characteristic member of the warm-water sublittoral formation (8), 
where it is commoniy associated with Grinnellia americana. 
(47) THE CYSTOCLONIUM ASSOCIATIONS. 
Cystoclonium purpurascens has a scattered distribution in both Bay and Sound 
(chart 254). It was found in 2% to 13 fathoms (most plentiful in 4 to 10 fathoms) 
attached to stones over sandy, shelly, and stony bottoms, occasionally over mud. The 
species rarely forms extensive patches but is conspicuous because of its large size; it 
is found in both the cool- and warm-water sublittoral formations. 
Cystoclonium purpurascens var. cirrhosum is abundant in the lower portion of the 
Bay and westerly portion of the Sound (chart 255). It was dredged in 1 to 17 fathoms 
(most plentiful in 4 to 12 fathoms) attached to stones and to larger alge over a bottom 
similar to that of the preceding species. The variety is much more luxuriant than the 
species and frequently forms large patches of vegetation; it clearly prefers the condi- 
tions of the cool-water sublittoral and is a prominent member of that formation (A). 
(48) THE CHAMPIA ASSOCIATION. 
Champia parvula is one of the most widely distributed algz of the region, occa- 
sionally forming extensive patches in the Bay and Sound (chart 256). It grows in 1 to 19 
fathoms (most plentiful in 4 to 12 fathoms) attached to stones, Zostera, and larger 
algae, over sandy, shelly, stony, and muddy bottoms; it is frequently found in shallow 
water along the shore. The species belongs to the warm-water sublittoral formation 
(B), being found most abundantly in sheltered regions. 
(49) THE LOMENTARIA ASSOCIATIONS. 
Lomentaria rosea is found only off the exposed points of Gay Head and Cuttyhunk 
(chart 257). It was dredged in 4 to 13 fathoms on stones, shells, and on larger alge, over 
sandy, shelly, and stony bottoms. The species is restricted to the cool-water sublittoral 
and although never abundant is one of the most characteristic members of this forma- 
tion (A). 
Lomentaria uncinata grows in the sheltered waters of the Bay and Sound (chart 258). 
It was dredged in 1% to 15 fathoms (most plentiful in 4 to 10 fathoms) over sandy, 
