Ceramiea.'] seirospora. 187 



25. Callith AMNION Daviesii, Agardh. 



Hab. Parasitical on the smaller Algse, such as Ceramium 

 ruhrum. 



The forms elegant, pencilled tufts, which give a richly 

 dressed appearance to the plant on which it fastens. Though 

 it is a little fellow of only three lines in height, it is quite 

 a gourmand, and has in Phyc. Brit, devoured, not only 

 Callitliamnion lanugmosum and ray little favourite Cal. 

 secundatiim, but also Callithamnioyi virgatulum, though 

 larger than itself. It is not uncommon on the west coast, 

 especially at Portincross, in rock-pools on Ceramium. 



Genus XXXVII. SEIROSPOEA, Harvey. 



Gen. Char. Frond rosy, filamentous ; stem articulated, one- 

 tubed, the articulations traversed by jointed filaments ; branches 

 jointed, one-tubed. Fruit, oval tetraspores disposed in terminal 

 monihform strings. PaveUse ? — Seirospora is from two Greek 

 words signifying cJiain-seed. — Harvey. 



1. Seirospora Griefithsiana, Harvey. (Plate YI. 

 fig. 24, a fine branch, natural size ; at the base, on the 

 right, a branchlet with terminal tetraspores ; and, on the 

 left, the tetraspores removed, more or less magnified.) 



