4 
Bay, Maine. Distinguished by the relatively large, branching 
plurilocular sporangia. 
EcrocaRPUS AECIDIOIDES Rosenvinge, Gronlands Havalger, 
894. fig. 27. A minute species, forming spots barely visible to 
naked eye, on old fronds of Laminaria species. The vegeta- 
tive filaments grow in the interior of the frond of the host plant ; 
when fruiting, the sori are formed directly under the epidermis, 
which is pushed upward and finally ruptured. Found at York 
Island, near Isle au Haut, Maine, July, 1894. 
DESMOTRICHUM UNDULATUM (J. Ag.) Reinke, Atlas, 15. p/. rz. 
Resembles a small Puxctaria, and grows commonly on Zostera 
marina in quiet bays. The Punctaria latifolia var. Zosterae, ot 
Farlow’s Manual, is probably in part identical with this species. 
I have found it on the coasts of Maine and Massachusetts, and Mr. 
Holden finds it at Bridgeport, Conn. Specimens from the latter 
locality are distributed in Phyc. Bor. Am. no. 129. In company 
with this species we generally find more or less of the following : 
D. sBatticum Kiitz. A much slenderer species, mostly of a 
single series of cells, ending in a long, colorless hair. See Reinke, 
Atlas, 15. p/. 72. The limits of species are very difficult to de- 
fine in this and the related genera, and it would not be difficult to 
arrange an uninterrupted series of specimens from the fine, Ecto- 
carpus-like D. scopulorum to the coarse, leathery Pwnctaria planta- 
ginea. 
RaLrsiA PUSILLA (Stromf.) Holmes & Batters (Stragularia pusilla 
Stromfelt, Notarisia, 3: 382. pl. 3. f. g. 1888). The smallest 
species of the genus and of quite different habitat from the others, 
which grow on rocks and woodwork, while this is epiphytic. The 
original description gives it as occurring on Laminaria; on the 
New England coast I have found it from Marblehead to Mount 
Desert, growing on Chaetomorpha aerea and C. Melagonium, form- 
ing thin, black “collars’’ around one or more cells in the upper 
part of a filament. | 
SCYTOSIPHON LOMENTARIUS COMPLANATUS Rosenvinge, Gronl. Hav. 
863. hea 
This variety, described from Greenland specimens, has been _ 
found by Mr. Holden growing abundantly and luxuriantly at ae 
Bridgeport, Conn. It is a spring plant, disappearing in early . y 
