MARINE 



OF BEAUFORT, N. C. 



519 



This species is distinguished from Halymenia floridana by its thicker, more gelatinous texture, its 

 looser structure , its papillate surface seen in surface view, its scarcity of heteromorphous " stellate ganglia" 

 in subepidermal view, and its less rosy color, sometimes with a greenish or yellowish tinge. Its cysto- 

 carps also appear to the naked eye larger and less dense than in H. floridana. The two species may 

 usually be distinguished with certainty, but one specimen (No. 22), having the structure of Halymenw 

 gelinaria and accordingly placed in that species, has the color and texture of Halymenia floridana. 



It is distinguished from Chrysymenia agardhii, which it resembles, by its more gelatinous texture, its 

 slightly thinner frond, with smaller, less numerous cells, and by its conspicuously papillate surface. 



The structure of the present species closely resembles that of the single specimen of Halymenia 

 latifolia that has been available to the author. 



This is the northern known limit of the species and of the genus. 



FIG. 44. Halymenia gelinaria, cross section of thallus 

 (microtome section from preserved material), X 240. 



FIG. 45. Halymenia floridana, cross section of thallus 

 (microtome section from dried material), X 240. 



FIG. 46. Halymenia floridana, cross section of thallus 

 (hand section from dried material), X 240. 



FIG. 47. Melobesia farinosa f . caUithamnioides, portion of 

 thallus as seen in surface view, X 44. 



4. Halymenia floridana J. Agardh. Figs. 45 and 46; PI. CXII, fig. 4b. 



Halymenia ligulata, Harvey, 1853, p. 192 (not H. ligulata of other authors). 

 Halymenia floridana, J. Agardh, 1894, p. 59. 

 Halarachnion t floridanum De Toni, 1905, p. 1655. 

 (Not P. B.-A. Nos. 749, 750.) 



Frond flat, 5 to 20 cm. tall, 4 to 10 cm. wide, borne on a short, narrow, filiform, conspicuous stipe 

 a few mm. long, at first ovate, entire, later forming numerous ovate lobes cuneate at the bases, tapering 

 toward the obtuse apices, finally laciniate, somewhat palmatifid; medulla traversed by many irregu- 

 larly branched filaments of irregular sizes, segmented occasionally, but not. conspicuously, frequently 

 anastomosing and forming numerous conspicuous stellate ganglia, cortex one to four cells thick, the 

 cells usually of fairly uniform diameter, cuticle persistent and conspicuous, surface smooth; cystocarps 

 occurring singly, appearing as minute dots scattered over the thallus, forming slight swellings on both 

 surfaces; texture thin, membranaceous; color dark rose or purplish pink. 



Florida; Bermuda. 



