MARINE ALGJE, OF BEAUFORT, N. C. 513 



Fronds moderately robust, terete, 4 to 25 cm. tall, about i mm. in diameter below, tapering toward 

 the apices, branching radial, cortex continuous almost to the apices of the branches; branches some- 

 times recurved, hairlike branchlets more or less abundant, especially over the upper parts of the 

 branches, about 0.5 to 1.5 mm. long, naked, except at the nodes, where they are surrounded by a 

 ring of cortical cells, simple and acuminate at the apices; segments of the branches about equal to the 

 diameter in length or somewhat longer, those of the hair branchlets 2 to 4 diameters long; tetrasporangia 

 borne singly or two to three together at the nodes of the hairlike branchlets; cystocarps two to three 

 lobed, terminal on short, lateral branches; texture flaccid or slightly rigid and brittle; color purplish 

 pink. 



Warm and temperate waters generally. 



Small fragments in tide pool on "Town Marsh," Beaufort, N. C., September, 1905, two large 

 masses on Bogue Beach, October, 1905, large, battered specimens in tide pool ("Mullet Pond") on 

 Shackleford Banks, August, 1907, few plants dredged from coral reef offshore, August, 1914 and 1915.' 

 Abundant on Zostera marina in Pamlico Sound, o to 30 cm. below low water, August, 1907, Ocracoke, 

 N. C. Few specimens on beach, August, 1909, Georgetown, S. C. 



This species is distinguished from the following one by absence of the club-shaped branches and 

 by the numerous fine, hairlike branchlets scattered over the frond and usually abundant on the younger 

 parts of the branches. It is variable in appearance, but good specimens are usually easily recognized. 

 It is not likely to be mistaken for any other species in this region. 



2. Spyridia clavata Kuetzing. 



Spyridia clavata, Kuetzing, 1841, p. 744. 

 Spyridia clavata, De Toni, 1903, p. 1435. 



Fronds slender or moderately robust, rather terete below, flattened above, 8 to 20 cm. long, about 

 i to 2 mm. wide, branching distichous, usually alternate, sometimes opposite, larger and smaller branches 

 intermixed, cortex continuous to the apices of the branches; smaller branches tapering toward the 

 bases, larger toward the apices, markedly club shaped, about 2 to 4.5 mm. long, apices acuminate or 

 obtuse; very fine, hairlike branchlets present, but not very conspicuous, naked, except at the nodes, 

 where they are surrounded by a ring of cortical cells, simple and acuminate at the apices; texture 

 gelatinous-cartilaginous, somewhat rigid ; color light pink with tinge of green or straw. ^ . 



North Carolina; West Indies; Senegambia. 



Several plants dredged from coral reef offshore, Beaufort, N. C., August, 1914. 



This species is distinguished from the preceding by its markedly club-shaped, small branches 

 and by the flattening present in the upper part of the frond. It sometimes resembles, in its gross appear- 

 ance, Chondria tenuissima, but is easily distinguished from this by its evident segments showing through 

 the cortex, resembling in this respect Ceramium rubrum. 



This is the northern known limit of the species. 



Genus 5. Ceramium Agardh. 

 Ceramium, Agardh, 1817, p. XXVI. 



Frond erect, terete, slender, of moderate size, branching profuse, regularly dichoto- 

 mous with forcipate apices, and bearing in addition more or less numerous lateral 

 branches; structure cellular, with a central axis composed of a row of large cells and 

 surrounded at the nodes or throughout by a more or less dense cortex whose cells become 

 smaller toward the surface, sometimes beset with spinelike hairs; tetrasporangia formed 

 from cortical cells at the nodes, naked or inclosed, often becoming prominent and pro- 

 truding, occurring singly or several together, sometimes forming a single or double circle 

 surrounding the node, triangularly divided; antheridia forming more or less expanded 

 irregular patches over the surface of the cortex on smaller branches; procarps occurring 

 in small numbers on the outer side of the upper dichotomies, bearing two carpogonia; 

 cystocarps lateral, sessile at the nodes, toward the apices of the branches, sometimes 

 appearing almost terminal, surrounded by several short, incurved branchlets, contain- 



