298 T. H. -r.UFFIIAM ON ANTPIKRIDIA. 



no other record, nor are any figures extant. Mr. Batters' dis- 

 covery at Berwick in Nov. 1889 was quite independent as 

 these remarks of Klitzing's had escaped his notice. This is a 

 striking instance of the necessity of searching for antheridia 

 where they are insufficiently known. 



Laurencia ohtusa Lamour. — The ultimate bianchlets of the 

 male plant are curiously wrinkled with sinuous transverse 

 ridges. The antheridia are formed in the cuplike hollow at 

 the apex of each branchlet, but it is necessary to dissect them 

 out. It is then seen that the hollow^ contains 10 or 12 dense 

 masses of male cells. Each has a peduncle which branches out 

 on all sides, and this is repeated at such short intervals that 

 there results an almost globular mass, 120-150 /x in diam. 

 The youngest and smallest masses are in the centre of the 

 hollow, and the oldest and largest bulge out at the top. Some 

 of them have branching filaments projecting above the mass. 

 The pollinoids are spherical, 6 fx in diam. (larger than any 

 described above), and are discharged from ellipsoidal cells a 

 little larger. (Swanage, Aug. 1890.) Harvey appears to have 

 seen the antheridia of this species (see remarks in Phyc. Brit.), 

 and Derbes and Solier have figured them (op. cit.) but not very 

 completely. 



Polysiphonia tirceolata Grev. — I found a few antheridia on 

 some tetrasporic plants. The male organs were near the 

 apices; the tetraspores lower down. The antheridia in this 

 species are mucronate, and of the character usual in this 

 genus. (Teignmouth, Aug. 1892.) 



In P. Brodicei Grrev. the antheridia are tapering, but not 

 mucronate, nor very obtuse. They are copiously borne at the 

 apices of the filaments. (Swanage, Aug. 1890.) 



Spermothamnion hermapJiroditum Nag. has been frequently 

 described and figured after him in botanical textbooks. 

 Almost invariably a short ramulus bearing a procarp with 

 trichogyne is accompanied by a single antheridium terminal on 

 a unicellular ramulus. The male body after maturity falls off 

 entirely. Although sometimes regarded as a variety of Sp. 

 Turneri Avesch. {Callifhamnion Turneri Ag.) I am inclined to 

 think it specifically different. The cystocarps are frequently 

 ialmost naked ; the antheridium seems to have a looser texture 

 than in Sp. Turneri; the tetraspores are generally single or 



