190 Rhodora [OCTOBER 
Ulva, Enteromorpha, Cladophora, Rhizoclonium, Anabaena torulosa, 
Oscillatoria margaritifera, Porphyra, and Ectocarpus. 
On Gull Island the northwest and west sides are comparatively 
bare of algae. Toward the northeast end large rocks are scattered 
as far out as one large boulder. The flora here is largely composed 
of rockweed, with Elachistea and Sphacelaria on the Fucus and 
Polysiphonia fastigiata on the Ascophyllum. Much Punctaria is 
present, bearing Isactis plana and Calothrix fuscoviolacea, with Poly- 
siphonia nigrescens and Mesogloia also common. On the eel grass 
is an abundance of Melobesia LeJolisii and Rhododermis Georgii. 
On the large boulder is a fine growth of Prasiola stipitata, and in a 
little pool on the top much Platymonas subcordiformis. 
On the east side rocks extend out beyond a patch of Spartina on 
the shore, and here, in addition to the species noted above, luxuriant 
Polysiphonia urceolata formosa, Dictyosiphon, and Punctaria are 
found. 
On the bar at the southeast end of Gull Island few algae are to be 
seen on the east side, where the bottom is covered with cobbles, with 
a few tufts of rockweed on the larger stones. On the west side, 
however, algae are abundant. The rockweeds bear Elachistea, Dictyo- 
siphon, and Mesogloia abundantly. In the deeper water, especially 
toward the northwest end, Melobesia is common on the eel grass, 
and much Chorda is also found. Covering much of the bottom is 
a heavy growth of Anabaena torulosa and Oscillatoria margaritifera. 
The smaller algae, besides being fouled with these species, are covered 
here and there with Calothrix confervicola. 
A comparison of the marine algae found with those listed by Jordan 
shows that there has been a considerable change in the marine flora 
since 1873. Excluding species not now recognized by systematists, 
Jordan listed 25 species which were not found in the course of the 
survey. Of these 8 belonged to the Chlorophyceae, 2 to the Phaeo- 
phyceae, and 15 to the Rhodophyceae. On the other hand the col- 
lections of 1923 show 43 species and 9 varieties not represented on 
Jordan’s list, of which 11 belong to the Myxophyceae, 9 to the Chloro- 
phyceae, 13 to the Phaeophyceae, and 19 to the Rhodophyceae. Of 
these, in addition to the Myxophyceae, which are very poorly repre- 
sented in Jordan’s list, 9 species are either very small or parasitic 
and likely to have been overlooked by Jordan at a time when know- 
ledge of such forms, at least in this country, was little advanced. 
