GENUS ^Microcladia^ ^M. Coulteri.^ Cylindrical, slightly flattened main stem; branches set uniformly and alternately, short at the base, gradually lengthening as far as the center, and from there diminishing to the apex of the stem, giving a leaf-like outline. The same mode of branching and the same outline are repeated in the branches. The ultimate divisions are like forked divisions, and are somewhat incurved. The plant is six to eight inches high, and in color is of many shades of red and pink. It is found in abundance on the Pacific coast at all seasons. (Plate XXXV.) ^M. borealis.^ Branches and branchlets placed on one side of arched main stems; secondary branches curved in opposite direction and bearing branchlets, also divided on one side only; color dark brown. It is found on the northern Pacific coast. (Plate XXXV.) [pg094] ORDER =CRYPTONEMIACEÆ= SUBORDER ~GLOIOSIPHONIEÆ~ GENUS ^Gloiosiphonia^ ("/Viscid tube/") ^G. capillaris.^ Frond six to ten inches high, solitary or in tufts; main stem cylindrical, solid above, hollow below; from about an inch above the base densely beset with short, wide-spreading branches arranged evenly and all around the stem; branches again branched in the same way; branches and branchlets attenuated at base and apex; soft, tender, juicy; shrinks much in drying. The species is easily recognized by its delicate gelatinous substance, tapering branchlets, and brilliant red color. It is found in early summer in tide-pools on the New England coast. SUBORDER ~GRATELOUPIEÆ~ GENUS ^Halymenia^ ^H. ligulata.^ Frond membranaceous, repeatedly and regularly divided in a forking manner; the larger divisions one half of an inch wide and growing very narrow at the top; four to five inches high, spreading in a fan-shape; color rose-red. It is found at Key West. GENUS ^Grateloupia^ ^G. Cutleria.^ Frond coarse, flat, variable; either simple, long, and narrow, or short and broad, tapering at both ends, or blunt at the apex, or deeply cleft into many segments; sometimes with leaflets along the edges; height two to three feet; color reddish-brown; in fading, changes to purple and green, and may be variegated. When simple, the plant resembles /Iridæa/. Found on the northern California coast. GENUS ^Prionitis^ ^P. lanceolata.^ Frond narrow, flat, smooth; leathery stems, which branch irregularly and sparingly from the edges; branches bordered with lance-shaped leaflets; color dark brownish-red; plant ten or more inches high, and varies considerably. (Plate XXXV.) There are other species, among them ^P. Andersonii^ (Plate XXXVI.); all are easily distinguished by the lance-shaped leaflets. Common on the Pacific coast. [Illustration: PLATE XXXV. Microcladia Coulteri. Microcladia Coulteri, magnified. Microcladia borealis. Prionitis lanceolata.]