V. GELIDIACE.E. 117 



2. Gelidium serrulatum, J. Ag. ; " caulescent, stem two-edged, naked below ; 

 frond three to four times pinnate ; pinnules dilated from a narrower base, cuneate- 

 linear, the younger serrulate at the margin, the fertile subsimple, obovate, serrated^ 

 curled and twisted, containing numerous tetraspores." J. Ag. Sp. Alg. 2, p. 472. 



Hab. Gulf of Mexico. At Guayra, Venezuela, Liebman. 



This is said to resemble a robust state of G. corneum, from ■which it is readily 

 known by the serrulated pinnules. 



3. Gelidium cartilagineum, Grev. ; root much branched ; fi'ond elongate (12 — 18 

 inches) two edged, purple or changeable, decompound-pinnate ; pinnas patent, with 

 rounded axils, linear, very entire, somewhat flexuous, twice or thrice compound ; 

 pinnules mostly opposite ; tetraspores in the incrassated tips of the ultimate 

 pinnules. Han: PJigc. Brit. t. 337. J- Ag. Sp. Alg. 2, p. 473. Kiitz. Sp. Alg. 

 763. Fucus cartilagineus, Turn. Hist. t. 124. E. Bot. t. 1477. 



Hab. California, D. Douglas ; Dr. Coulter ; Lieut. Wood. (v. v.) 



Root a mass of much branched, rigid fibres. Fronds in our Californian speci- 

 mens about twelve inches long, a line in diameter, compressed, two-edged, becoming 

 flatter upwards, three or four times pinnate. Stems naked in the lower half, pin- 

 nated above the middle ; primary pinnw elongate, patent, alternate or sub-opposite, 

 naked below, pinnate or bi-tri-pinnulate above. All the lesser pinnules issue at 

 very obtuse angles, with a distinctly rounded axil ; they are either alternate or 

 opposite, sometimes quite simple, sometimes decompound. Specimens with teti-a- 

 spores have generally more sub-divided pinnules, the tetraspores being lodged in 

 the thickened, gland-like apices. Substance cartilaginous, horny when dry. When 

 growing the colour is very dark brownish purple-red, but on exposure to the air it 

 changes through various brilliant tints of red, orange, yellow, and greenish to a 

 horny white. It does not adhere to paper in drying. 



4. Gelidium Coulteri ; frond very narrow, piano-compressed, sub-naked below, 

 decompound. pinnate above ; pinna; close together, distichous, once or twice com- 

 pounded, pinnules tapering to the base, acute, the fertile ones spindle-shaped, acute- 

 and often aculeate. 



Hab. California, i)/-. Coulter, (v. s. in Herb. T.C.D.) 



Densely tufted, three or four inches high, less than half a line in breadth, com- 

 pressed or two-edged, bare of branches below, closely pinnate above the middle ; 

 the pinnae one or two lines apart, of various lengths, the lowest longest and most 

 compound, once or twice piunulated. Pinnul(je closely set, distichous, the lower 



