464 BULLETIN OF THE BUREAU OF FISHERIES. 



KEY TO GENERA. 



a. Asexual spore formed from the contents of a vegetative cell without division, sexual 



reproduction apparently lacking 3- Goniotrichum (p. 465). 



oo. Asexual spore formed from the smaller of two cells arising from the unequal division of a 



vegetative cell by an oblique wall, sexual reproduction usually present b. 



b. Thallus consisting of erect filaments 4- Erythrotrichia (p. 466). 



bb. Thallus consisting of branched filaments creeping on or in the surface of other algae, 



and more or less fusing to form a single-layered disk 5. Erythrocladia (p. 466). 



ooo. Asexual spores formed by approximately equal division of a vegetative cell (some- 

 times without division), sexual reproduction present c. 



c. Thallus filiform x. Bangia (p. 464). 



cc. Thallus membranaceous, flat 2. Porphyra (p. 464). 



Genus i. Bangia Lyngbye. 



Bangia, Lyngbye, 1819, p. 82. 



Thallus erect, filiform, unbranched, attached by an expanded base, more or less 

 thickened above, terete, commonly irregularly constricted, sometimes tubular and hollow 

 above. Asexual spores, formed from the entire contents of vegetative cells or from 

 cells formed by one (or sometimes two) divisions of vegetative cells, are discharged into 

 the water and germinate immediately. Numerous spermatia formed by repeated 

 division of vegetative cells which function as antheridia. Eggs arising singly from the 

 entire contents of enlarged vegetative cells. Fertilized eggs divide into a few (usually 

 eight) spores, which are discharged into the water and apparently germinate imme- 

 diately. Asexual and sexual organs borne on the same or on different individuals, male 

 and female organs produced on the same or different individuals. 



About 10 species described, but not sharply separated, mostly marine, occasionally 

 in fresh water. 



Bangia fusco-purpurea (Dillwyn) Lyngbye. 



Conferva fusco-purpurea, Dillwyn, 1809, pi. 92. % 



Bangia fusco-purpurea, Lyngbya, 1819, P. 83, pi. 24 C. 



Bangia fusco-purpurea, Farlow, 1882, p. 112. 



Bangia atro-purpurea, var. fusco-purpurea, DeToni, 1897, p. 112. 



P. B.-A. Nos. 87. 2084. 



Thallus filamentous, erect, 0.5 to 15 cm. long, attached to rocks, etc., variable in color and size, 

 pink to purple, younger filaments composed of one or two rows of cells, older filaments forming a hollow 

 tube. 



Cold and temperate North Atlantic and Pacific; Mediterranean. 



Abundant between tide lines on rocks of Shackleford jetty, Beaufort, N. C., May, 1007, and fairly 

 abundant on Shackleford and Fort Macon jetties, April, 1908; probably occurs from December to May. 



Specimens vary greatly in appearance on account of their differences in size and color; the filaments 

 vary from a fineness that is indistinguishable to the naked eye to the thickness of a coarse hair; the 

 cells vary greatly in diameter. 



This is the southern limit reported for the species, but specimens are known from points farther 

 south, and the species will probably be found to extend along our entire coast during the winter. 



Genus 2. Porphyra Agardh. 



Porphyra, Agardh, 1824, p. XXXII. 

 Porphyra, De Toni, 1897, p. 13. 

 Wildemania, De Toni, 1897, P- 20. 



Thallus erect, foliaceous, flat and thin, margin entire, lobate or laciniate, often 

 undulate, attached by a basal disk, base substipitate; at first consisting of a simple 



