CaUithamnion ] ALG.E RHODOSPERME^E. 215 



branches densely raraulose, hairy below, plumulate above ; 

 plumules crowded, quadrifarious, oval, simply pinnate ; pinnae 

 acute, basally attenuate, erecto-patent ; articulations 2 3 times 

 longer than broad ; capsules elliptical, minute, on short lateral 

 processes of the pinnulae. Harv. in Hook. Br. Ft. v. ii. p. 342. 

 Conf. tetrica, Dillw. t. Si. E. Bot. #.1915. 



Rocky shores ; common on our western and southern coasts. 2 8 

 inches long, forming dense ropy tufts, of a dull red-brown colour. 



8. C. tetragonum, Ag. Square-stalked CaUithamnion. Stem 

 robust, naked below, decomposito-pinnatedly branched; branches 

 patent, set with short, alternate, spreading plumules, which are 

 pinnate below, and fasciculately multifid above ; apices obtuse, 

 with a mucro ; articulations once and half as long as broad ; 

 joints contracted. Harv. in Hook. Br. Fl. v. ii. p. 343. Conf. 

 tetragona, Dillw. t. 65. E. Bot. t. 1690. 



On the larger Algae, not uncommon. 3 8 inches high, dull red, 

 becoming brownish in the herbarium. The robust, cartilaginous, and 

 many times pinnate stems, with the short articulations, and ramuli 

 contracted at the apex, (thus suddenly acuminate,) distinguish this 

 species. 



9. C. granulatum, Ag. (?) Warted CaUithamnion. Stem 

 robust, naked below, pinnatedly branched ; branches erecto- 

 patent, set with short, subquadrifarious, erect plumules, which 

 are pinnate below, and multifid and level-topped above ; pin- 

 nules subulate, very erect and close pressed ; articulations of 

 the ramuli twice as long as broad. Harv. in Hook. Br. FL v. ii. 

 p. 343. Ag. Sp. Aly. v. ii. p. 177. ? 



At Kilkee, County of Clare, on Codium tomentosum. 2 4 inches 

 high. Stems mostly simple, set with alternate branches; each frond 

 with a lanceolate outline. Colour brownish-red. It must be confessed 

 that this borders very closely, indeed, on the preceding, from which it 

 is best distinguished by its more erect and level-topped plumules, subu- 

 late pinnules, and rather longer joints. But, after all, perhaps, it is not 

 sufficiently entitled to specific rank. Having seen no authentic spe- 

 cimens of Agardh's plant, I am unable, with certainty, to quote his work, 

 but his description agrees pretty fully with our Irish specimens. 



10. C. Grevillii, Harv. Grevilles CaUithamnion. Slender, 

 sparingly and distichously branched ; plumules linear-obovate, 

 round-topped ; pinnae erect ; the lower ones short and spine-like 

 the upper long, branched at top ; articulations of branches 2 3 

 times, of pinnules once and half as long as broad. Harv. in 

 Hook. Br. Fl. v. n.p. 345. C. roseum, Grev., Fl. Edin. p. 311. 

 (not of Both.) 



On rocks and Algae in the sea. Bantry bay ; Miss Hutchiiis. 12 

 inches high, forming small tufts. Branches long, their lower part fur- 

 nished with short irregular ramuli, their upper half distichously plu- 

 mulate. Plumules long, narrow- obovate ; upper pinnae alternately 

 branched at top. Colour purplish -red. 



