Collins and Howe: Species of Halymenia 175 



more homogeneous refringent protoplasts; cortex and subcortex 

 of frond rather distinctly filamentous; subcortex consisting of a 

 close network of anastomosing filaments, the stellately branched 

 nodal cells mostly 13-20^1 in diameter; cortex 1-4 cells thick, the 

 superficial cells (protoplasts) 3-10 m in diameter in surface view, 

 mostly obtuse and more or less isodiametric, sometimes broader 

 than high, or, 1.5-2 times higher than broad and subacute, often 

 segregated in groups of 2-8, their outer walls very gelatinous and 

 deliquescent; tetrasporangia (protoplasts) 18-26/1 X 13 m, the 

 spores decussately paired; cystocarps numerous, minute, com- 

 monly slightly protuberant on one face, the spore-mass turbinate, 

 120-240 IX in diameter. 



Florida: Unattached, Jupiter Inlet, Mrs. G. A. Hall, Sep- 

 tember 14, 1896 (Phyc. Bor.-Am. 74Qb and 749c, as H . floridajta) ; 

 M. A. Howe 1252-1255, October 13, 1902; Indian River Inlet, 

 Mrs. G. A. Hall, May, 1899 (Phyc. Bor.-Am. 749a, as H.Jloridana, 

 and 750, as H. floridatia, forma dentata); Key West, Mrs. G. A. 

 Hall. 



North Carolina: Bogue Beach, Beaufort, W. D. Hoyt, 

 August 12 and 16, 1^07. 



Type: Jupiter Inlet, Florida, October 13, 1902, M. A. Howe 

 1252, sheet C, in herb. N. Y. Botanical Garden. 



The plant is known locally in the Jupiter Inlet region as the 

 "beefsteak" seaw^eed. In form and color of the thallus, as well 

 as in size and form of the cystocarps, Halymenia Gelinaria bears a 

 remarkable resemblance to H. floridana; in fact, for two species 

 that dififer so much in the structure of the cortex, the similarity 

 is astonishing. The affinities of H. Gelinaria are, however, clearly 

 Avith H. Floresia, a species that it resembles much less in general 

 habit. From H. Floresia, it differs chiefly in forming broad, 

 entire or subentire membranes, which may reach a length or width 

 of 60 cm., and in the less often acute, more isodiametric, super- 

 ficial cells. H. Floresia, in typical forms, was found floating with 

 it in Jupiter Inlet {Howe I2ji) without intergrading conditions. 

 When lobules, proliferations, or teeth occur in H. Gelinaria, they 

 are very irregularly disposed, while in H. Floresia the branching 

 is manifestly pinnate, or rather, bi-tri-pinnate. The main axes 

 in H. Floresia may vary a good deal in width, but we have never 

 seen them any broader than 7 cm. and they are rarely more than 



