MARINE ALG.E OF NEW ENGLAND. 127 



Our most rolmsi aiul t •oai'sest species, not unct>mmon in Lon;^ Ishunl Soiiiid, hut not 

 yet recordetl north ot"CaiH> Cod. The color is dark, and in the water ahuost Idack, 

 and the suhstance is rather spongy, the plant not collapsing when removed from the 

 water, a^^ do most of the New England species of the genus. 



C. Baileyi, Ilarv. {C. Baileyi, llarv., Xor. Am. Bor., Part III. PI. 

 35 b.—Dorythamnion Baileyi, Na^g.) PI. XI, Figs. 1-2. 



Fromls momecious, two to four inches lii^^li, setaceous, shrub-like, 

 pyramidal in outline, color purplish red, main tilaments densely corti- 

 cated, the rest monosiphonous ; main axis percurrent, attached by a 

 disk, pinnate with long, undivided, alternate branches, which are once 

 or twice pinnate, the ultimate divisions beset on all sides with rather 

 slender, tlexuous, recurved or incurved, fasciculate branches ; cells 

 several times longer than broad ; tetraspores tripartite, sessile on the 

 upper branchlets ; antheridia in tufts on the upper internodes ; favellie 

 binate. 



Var. LAXA. 



Cortications less marked than in the type, branchlets long and slen- 

 der, di\isions widely spreading below, fostigiate at the apex. 



On Zostera, stones, sponges, and algie below low-water mark. 



Common from New Jersey to Cape Cod ; Boston Bay, Harvey ; Port- 

 land, C. B. Fuller. 



As is suggested by Harvey in the Nereis Am. Bor.. the present species is not only 

 very variable in habit, but it is also ditficult to distinguish some of the forms from C. 

 tetragonum. We are inclined to believe that it would be better to consider the pres- 

 ent species as a delicate form of C. tetragonum, in which the cells are longer and more 

 slender, the branchlets less dense and robust, the color less incUned to blackish, and 

 the substance more delicate. K we are to unite Hhodomela subfitsca, R. gracilis, and 

 E. Rochet in one species, as has been done by Agardh, with good reason as it seems, it 

 would be equally correct to unite C. Baileyi and C. tetragonum, since the dilferenceiu 

 habit might result from variations of habitat and season. With us, the form here 

 referred to the typical C. Baileyi is more common than C. tetragonum, and is found on 

 wharves, on Zostera, shells, and stones in rather warm waters and sheltered places, 

 while C. titragonum frequents places where there is a current of water, or grows on 

 alga? in somewhat exposed pools. The var. laxa has a diffuse ramification and the 

 cortications are not prominent, and we at one time supposed that it might bo the C. 

 Dietcite of the Nereis, as far as we could recollect the specimens of that species in the 

 Harveyan Herbarium at Dublin. In such cases, however, it is not safe to trust to 

 one's memory, and in the present article we are unwilling to express an opinion about 

 C Dit:t2i(F. 



Sect. III. Byssoid^e. 



Branching monopodial or dichotomous, cortications present at the basCy 

 ultimate branches decompoinvJ, very delicate^ usually ending in a hyaline 

 hair, 



C. BYSSOIDEUM, Am. (C. byssoideum^ Phyc. Brit., PI. 2G'J.—Phlr. 

 bothamnion byssoideSj Kiitz. — Poecilothamnion byssoidcum, Nieg.) 



