124 CH0RDARIACEJ3.— Chordaeia. iv. 



filaments of the periphery club-shaped. J. Ag. Sp. Alg. vol. 1, p. QQ. Kiitz. Sp. 

 Alg. p. 546. Harv. Phyc. Brit. t. 111. Fucus flagelliformis, Turn. Hist. t. 85. E. 

 Bot. t. 1222. 



Hab. On rocks, stones, and the smaller Algae between tide-marks. Common on 

 the shores of the Northern States. Newfoundland, Lenormand. Halifax, W. H. H. 

 Newport, R. I., Prof. Bailey, Mr. Olney, &c. Boston, G. B. Emerson. Staten 

 Island, N. Y. (v. v.) 



Fronds 1 — 2 feet long, as thick as bristle, mostly with an undivided leading stem, 

 which is densely set throughout its whole length with crowded or fasciculate lateral 

 branches. These branches are several inches long, of the same thickness as the 

 stem, straight or nearly so, and usually unbranched and quite naked : sometimes 

 they have each a few distant, spreading, straight ramuli ; and sometimes they 

 are as densely beset as the stem with such ramuli. The substance is firmly 

 cartilaginous and elastic, the surface lubricous, and if the plant be allowed to 

 remain some hours in fresh water, a very considerable quantity of mucus and some 

 colouring matter will be given ofi". The colour is always very dark olivaceous 

 brown. In young specimens, the whole frond consists of the cellulo-fibrous axis, 

 composed of a dense network of anastomosing threads ; there is then no periphery ., 

 or merely an outward coating of dark-coloured cells. As the plant enlarges, the 

 surface-cells grow out, by repeated cell-division, into moniliform peripheric threads, 

 which form a complete covering or pile to the frond. These peripheric filaments are 

 club-shaped, the cells of which they are composed gradually increasing in size, from 

 the base to the apex of the filament. Spores, concealed among the threads of the 

 periphery, are abundantly produced by almost every full-sized individual. When 

 growing, the whole frond is clothed with fine, colourless, jointed hairs, which give 

 the branches, as seen through the water, a feathery appearance. 



2. Chord ARIA divaricata, Ag. ; frond irregularly divided ; branches divaricating, 

 subdichotomous, flexuous, furnished with scattered, short, very patent, mostly 

 forked ramuli ; filaments of the periphery capitate. /. Ag. Sp. Alg. vol. 1, p. 65. 

 Harv. Phyc. Brit. 1. 17. Mesogloia divaricata, Kiitz. Sp. Alg. p. 545. (Tab. XI. A.) 



Hab. On the smaller Algas, etc., at and below low-water mark. Shores of Long 

 Island Sound, Stonington, Prof. J. W. Bailey. Newport, R. I., 3fr. S. T. Olney. 

 Dr. Durkee. Green Port, Long Island, Prof. J. W. Bailey and W. H. H. New 

 Bedford, Mr. Congdon. (v. v.) 



Fronds tufted, one or two feet long or more, not a line in diameter, very much, 

 but irregularly branched. Sometimes there is a leading stem, with lateral branches, 

 and sometimes the frond is broken up from the base into many principal divisions. 

 The branches are of various lengths, subsimple or rejjeatedly forked. They spread 

 at ■wide angles, and their divisions are equally patent, the intermediate spaces being 



