MARINE Al^GM OF BEAUFORT, N. C. 485 



On our coast G. confervoides is the more southern form, being recorded for only one locality north 

 of Long Island Sound. At Beaufort G. confer-voides occurs mainly in the harbor and has been found 

 only from April to November; G. multipartita occurs mainly on Fort Macon and Shackleford jetties 

 and remains throughout the year. 



Genus 2. Hypnea Lamouroux. 



Hypnea, Lamouroux, 1813, p. 131. 



Frond filiform, rather terete, virgately or divaricately, more or less richly branched 

 on all sides, often with numerous short, spinelike branchlets; fertile and sterile specimens 

 often very different in appearance; structure cellular, traversed by a more or less evi- 

 dent segmented central axis, inner cortex dense, composed of larger cells within, smaller 

 ones toward the surface, outer cortex thin, composed of small vertical cells arranged in 

 subsingle series; tetrasporangia scattered, embedded in the thickened outer cortex of 

 slightly swollen ultimate branchlets, zonately divided; cystocarps almost spherical, 

 prominent on ultimate branchlets, pericarp fairly thick, sometimes perforated by an 

 apical pore, sometimes opening only by the separation of cells at the apex, attached to 

 the base of the cystocarpic cavity by a network of filaments, gonimoblast arising from 

 the base of the cystocarpic cavity, much branched, attached here and there to the net- 

 work of sterile filaments and at these points giving off radiating tufts of short filaments 

 whose end cells form short chains of carpospores; antheridia arising on the surface, 

 forming a row of four spermatia from each spermatangium ; tetrasporangia, cystocarps, 

 and antheridia borne on different plants. 



About 25 species in temperate and tropical seas. 



Some of the species are easily distinguished, but some are separated by slight (per- 

 haps doubtful) characters and are very difficult to determine. Determination is made 

 still more difficult by the diversity in different forms of the same species, the cystocarpic 

 plants of different species being said in some cases to resemble each other more than do 

 the cystocarpic and tetrasporic plants of the same species. A revision of the genus is 

 needed, and such a study will probably separate the species along different lines from 

 those used at present. 

 Hypnea musciformis (Wulfen) Lamouroux. PI. C; PI. CI, figs, i and 2. 



Fucus musciformis, Wulfen, 1789, p. 154, pi. 14, f. a. 

 Hypnea musciformis, Lamouroux, 1813, p. 131. 

 Hypnea musciformis, Harvey, 1853, p. 123. 

 Hypnea musciformis, Farlow, 1882, p. 156. 

 Hypnea musciformis, De Toni, 1900, p. 472. 

 P. B.-A~. Nos. 196, 2185. 



Fronds filiform, 4 to 50 cm. tall, virgately or divaricately, more or less richly branched, branches 

 long, virgate, and rather sparingly clothed with small subulate branchlets, or short, bearing numerous 

 short branches which are densely covered with minute, spinelike branchlets; apices of the branches 

 often thickened and recurved to form tendrils, either naked or bearing short branches on their convex 

 surfaces; tetrasporangia immersed in the thickened outer cortex, scattered over swollen portions at or 

 near the bases of small subulate ultimate branchlets, zonately divided; cystocarps prominent, usually 

 on small spinelike or subulate ultimate branchlets; cystocarpic and tetrasporic plants sometimes 

 differing in habit; color dark green to light reddish green. 



Warm and temperate seas. 



Very abundant on Fort Macon jetties and in harbor, Beaufort, N. C. ; less abundant on Shackleford 

 jetties, attached to rocks, shells, and Zostera, from low water to 60 or 90 cm. below low water, fruiting, 

 May to October, less abundant and usually sterile, November to April; one plant dredged from coral 

 reef offshore, Beaufort, N. C., August, 1915; abundant in Newport River near Green Rock, in North 



