10 SOME NEW BRITISH MARINE ALG^. 



found at Falmouth, at the meeting of the Linneau Society on 

 Nov. 21st, 1895. 



Trailliella, nov. gen. Fronds composed of monosiphonous, 

 branching, jointed filaments. Primary filaments procumbent, 

 attached to the substratum by disc-shaped cells. Secondary 

 filaments arising from the primary filaments, erect, br.iuching. 

 Tetraspores immersed, formed from a portion of the cell-contents 

 of cells in the continuity of the frond, irregularly cruciate ; 

 cystocarps and antheridia unknown. The tetraspores are formed 

 in an analogous manner to the monospores of Ilhuduchute [ride 

 Bornet, Les Ahjues de P. K. A. Sclwusboe, p. 361). The cell 

 in which a tetraspore is formed swells, and its cellular contents 

 divide longitudinally into two parts of unequal size, the larger 

 of the two parts becomes darker in colour, more opaque and 

 granular, and at the same time increases in size until finally it 

 fills almost the entire cell, when it divides into two parts by a 

 transverse division, and ultimately forms an irregularly cruciate 

 tetraspore. The systematic position of the genus must of course 

 remain doubtful so long as the cystocarps are unknown, but in the 

 meantime the genus may be placed next to SpermotJunnnion. 



Trailliella intricata, nov. sp. Fronds forming dense, rose-red 

 or brownish-red tufts. Primary filaments 30-40 /x thick, irregularly 

 branching, attached by disc-shaped cells. Secondary filaments 

 erect, ^-1\ in. high, and of nearly equal diameter (30-45 /x) 

 throughout, simple or branching, more or less naked below, pin- 

 nate above, witli alternate or subsecund spreading branches of 

 almost the same diameter as those from which they arise, tapering 

 at the apex to about 20 /x. Cells of both the primary and secondary 

 filaments 1^-2^ times longer than broad, more or less swollen in 

 the middle ; in most of the cells one of the upper corners is occu- 

 pied by a small roundish or triangular refractive colourless body 

 12-15 /x in diameter, which is probably analogous to the refractive 

 bodies so often found in species of Antithamnion. Tetraspores 

 immersed in the swollen cells of the secondary filaments, 50-60 /x 

 in diameter, solitary or 3-o together, formed from successive cells 

 of the filament, separated from the apex of the filament by from 

 3 to 15 unchangeil cells. Plymouth, October, 1895, G. Brehner. 

 Studland, Sept. 1890, E.M.Holmes: Sept. 1895, E.A.B. 



This very interesting species has long been known in a barren con- 

 dition, and is the Spermothamnion Turneri f. intricata of Mr. Holmes's 

 and my Revised List, and I have every reason for believing that it is 

 S. intricatum J. Ag. It was reserved for Mr. Brebner, however, to 

 discover the tetraspores, which are placed quite differently from 

 those of any other member of the Ceramiea; known to me, thus 

 necessitating the removal of this plant to a new genus ; and I have 

 seized the opportunity to connect the name of my friend Mr. G. W. 

 Traill, the well-known algologist of Edinburgh, with the British 

 Marine Flora for which he has done so much. I must here express 

 my regret that Mr. Brebner has not seen his way to allow any of 

 the new genera discovered by him to bear his name. If Mr. 

 Brebner goes on as he has commenced at Plymoutb, however, 



