MARINE ALG^l OP NEW ENGLAND. 123 



On submerged algae. 



Eastport, Maine, W. G. F.; Portland, Maine, G. B. Fuller ; Glouces- 

 ter, Mass., Mrs. Bray and Mrs. Davis; South Boston, Dr. Durkee; 

 Northern Europe. 



A beautiful and easily distinguished species, found only in the colder waters of the 

 Atlantic, a variety occurring as far south as South Barbara, on the coast of California. 

 It is apparently not uncommon in spring from Boston northward, sometimes occurring 

 in company with C. Pylaiscei. It is rare, however, on the northern coast of Scotland. 

 It is easily distinguished from its allies in this latitude by the simple, subulate, sec- 

 ondary branches with which the main branches are clothed throughout. 



0. PyIjAis^ei, Mont. (Wrangelia Pylaiscei, Ag. Sp. — G. Pylaiscei, 

 Ner. Am. Bor., Part II, PI. 36 o. — Pterothamnion Pylaiscei, Naeg.) 



Fronds three to six inches long, main branches alternately decom- 

 pound, secondary branches short, rather stout, opposite, distichous, 

 once or twice pinnate with short subulate ramnli ; tetraspores cruciate, 

 sessile on the ramuli j favellae binate on the upper branches. 



On wharves and algae below low-water mark. 



Orient, L. I., Miss Booth ; Wood's Holl, Mass. ; and common from 

 Kahant northward. 



A common species of the Atlantic coast from Boston northward, but much less 

 abundant southward. It is found early in the spring on wharves and washed ashore 

 with other algae, but in the summer it is only seen in a dwarfed and battered condi- 

 tion. It is sometimes found in company with C. Americanum, and it is by no means 

 beyond a doubt that the two species are really distinct. In G. Pylaiscei the fila- 

 ments are more robust, and the cells themselves shorter and broader than in C. 

 Americanum, the main branches are less decompound and spreading, and the apical 

 branches are more erect and compact. It is, however, in the secondary branches 

 that the difference is best seen. In C. Pylaiscei they are short and thick, and the ulti- 

 mate divisions are broadly subulate. In C. Americanum they are long, slender, and 

 flexuous. Those who have only seen the typical forms of the two species would 

 scarcely believe that they were not very distinct species. The collector, however, 

 especially on our northern coast, often finds transitions between the two. At the time 

 the Nereis was written the cystocarpic fruit was unknown, and the species seemed to 

 Agardh to belong rather to the genus Wrangelia. The fruit, which is not uncommon 

 in the spring, is distinctly the same as in Callithamnion, and is a true favella. The 

 antheridia differ from those of C. corymbosum and its allies. Instead of forming ses- 

 sile, hemispherical tufts on the internodes of the branches, as in the last-named spe- 

 cies, the antheridia of C. Pylaiscei are in the form of rather loosely branching tufts 

 inserted at the nodes of the secondary branches, and occupy the position of the ulti- 

 mate branches, reminding one somewhat of the antheridia of C. graniferum, Menegh., 

 figured by Zanardini in Phycologia Adriatica, PI. 11, or the figure of C polysper- 

 mum in Phycologia Britannica. As far as our observations go, the antheridia and 

 cystocarps of the present species are on different individuals. The color, when dried, 

 is usually somewhat brownish, and decidedly less rose-colored than in C. Americanum. 



C. Americanum, Harv., Nereis Am. Bor., Part II, p. 238, PI. 36 a. 

 (Pterothamnion Americanum, ISTseg.) 



Fronds three to six inches long, capillary, main branches alternately 

 many times branched, ultimate divisions plumose, secondary branches 



