BIOLOGICAL SURVEY OF WOODS HOLE AND VICINITY. 
Castagnea virescens. 
*Chordaria flagelliformis. 
*Leathesia difformis. 
*Mesogloia divaricata. 
*Ralfsia clavata. 
*Chorda filum. 
Laminaria Agardhii. 
Laminaria Agardhii 
tata (0). 
Antithamnion americanum (0). 
Callithamnion Baileyi. 
C. byssoideum. 
C. corymbosum. 
*Ceramium rubrum. 
*C. strictum. 
*Griffithsia Bornetiana. — 
var. vit- 
*Chondria tenuissima. 
C. tenuissima var. Baileyana. 
*Dasya elegans. 
Polysiphonia elongata. 
P. fastigiata (0). 
*P. nigrescens. 
*P. variegata. 
*P. violacea. 
Actinococcus subcutaneus. 
Ahnfeldtia plicata. 
*Chondrus crispus. 
*Phyllophora Brodizi. 
P. Brodizi var. catenata (0). 
*P. membranifolia. 
Sterrocolax decipiens (0). 
471 
*Agardhiella tenera. _ 
Cystoclonium purpurascens. 
C. purpurascens var. cirrho- 
sum (0). 
*Champia parvula. 
*Lomentaria uncinata. 
Rhodymenia palmata (0). 
*Grinnellia americana. 
Gloiosiphonia capillaris (0). 
Polyides rotundus. 
Corallina officinalis. 
Hildenbrandia prototy pus. 
Melobesia farinosa. 
M. membranacea (0). 
M. pustulata. 
The warm-water sublittoral formation of the summer is known not only from the 
dredgings in the deeper waters, but also from many observations in the shallow waters 
at a number of points at or near Woods Hole, where the algal flora along shore has 
been studied by the writer for some ten summers. Extensive studies along shore have 
not been possible in the regions of the cool-water sublittoral formation (that is, in the 
lower portion of Buzzards Bay and westerly portion of Vineyard Sound), and the flora 
of the shallow water is known only at a few points, such as Gay Head, portions of Cutty- 
hunk, and Penikese. 
It is interesting to note that a considerable number of species in the above lists are 
restricted wholly or largely to shallow water in a zone from low-water mark to a depth 
of 3 to 6feet. The characteristic alge in this zone of the upper warm-water sublittoral 
are: 
Leathesia difformis. 
Mesogloia divaricata. 
Chzetomorpha linum. 
Cladophora, the species in the 
Polysiphonia fastigiata. 
P. fibrillosa. 
above lists. Ralfsia clavata. P. variegata. 2 
Ectocarpus, the species in the Chorda filum. P. violacea. 
above lists. Callithamnion Baileyi. Chondrus crispus. 
Pylaiella littoralis. 
Sphacelaria cirrhosum. 
S. radicans. 
Punctaria plantiginea. 
Castagnea virescens. 
Chordaria flagelliformis. 
C. Baileyi var. laxum. 
Ceramium rubrum. 
Chondria dasyphylla. 
C. sedifolia. 
C. tenuissima. 
C. tenuissima var. Baileyana. 
Champia parvula. 
Lomentaria uncinata. 
Grinnellia americana (on piles). 
Melobesia farinosa. 
M. pustulata. 
The algz listed in the Zostera formation (c) may also properly be included in this, 
the upper warm-water sublittoral formation. 
The summer temperature of the water is undoubtedly the chief factor in determining 
the warm-water sublittoral formation asa whole. The degree of exposure to wave action 
or tide currents and the character of the attachment are of course important factors 
affecting the local distribution of the alge along the shores. Thus, the vegetation off 
exposed points, as at Nobska or on the ledges in the passage of Woods Hole, is subjected 
to conditions very different from those of neighboring sheltered coves. As stated before, 
the summer temperature in Great Harbor, Woods Hole (as shown by daily averages 
