THE MARINE ALGiE OF NEW ENGLAND. 145 



ternal, globose, sessile or pedicellate, containing within a thick peri- 

 carp several irregular masses of spores imbedded among the cells of the 

 frond ; spores discharged by a narrow carpostome. 



The genus comprises eight or nine species of the North Atlantic and Mediterranean, 

 one species, P. Clevelandii, being found on the coast of California. The species are 

 dark red, rather coarse and rigid, not adhering to paper, and are very apt to be cov- 

 ered with Bryozoa. They inhabit rather deep water, and are characterized by their 

 external fruit, the tetraspores being arranged in nemiathecia or warts composed of 

 densely packed filaments, each cell of which becomes a cruciate tetraspore. Some of 

 the broader forms pass with collectors for species of Iihodymenia. 



P. Brodicei, Ag. ; Phyc. Brit., PI. 20. 



Stipes cylindrical at base, compressed upwards, branched, the branches 

 expanding into oblong or wedge-shaped, simple or forked, membrana- 

 ceous laminae, often proliferous at the summit ; cystocarps globose, ses- 

 sile on the laminae ; nemathecia spherical, pedunculate, at the tips of 

 the laininae. 



In five to ten fathoms of water. 



Newport, R. I. ; Wood's Holl, Mass. ; and common from Nahant north- 

 ward. 



P. membranifolia, Ag. ; Phyc. Brit., PI. 1G3. 



Stipe cylindrical, filiform, branched, the branches expanding into 

 broadly wedge-shaped bifid or dichotomous lamina3 ; cystocarps ovoid, 

 stipitate, rising from the branches or laminae; nemathecia forming 

 broad, dark-colored, convex patches in the center of the laminae. 



In deep water on stones. 



Common from Long Island Sound northward; North Atlantic. 



Our two species of PhyUopliora are perfectly easy to identify when tetrasporic speci- 

 mens are obtained. P. Brodicei is a larger plant than P. membranifolia, and the lainiuoe 

 are longer and larger and less broad at the base than in P. membranifolia. P. Brodicei 

 varies considerably, however, and in the spring the bright-red broad laminae are often 

 broken from the stipes and washed ashore, when they might be mistaken for some 

 species of Rhodymcnia. 



GYMNOGONGRUS, Mart. 



(From yvfivog, naked, and yoyypog, an excrescence.) 



Fronds dark red or purple, carnoso-coriaceous, terete, compressed or 

 fiat, dichotomous, composed of a medullary stratum of roundish, angu- 

 lar, colorless cells and a cortical stratum of closely packed short fila- 

 ments formed of small colored cells; tetraspores cruciate, borne in 

 hemispherical nemathecia; cystocarps immersed in the swollen frond, 

 consisting of several irregular masses of spores imbedded among the 

 cells of the frond ; spores discharged by a carpostome. 



A genus of about thirty species, found principally in the warmer parts of the world, 

 all rather coriaceous, but not attaining any great size. The genus is distinguished 



S. Miss. 59 10 



