200 ALGE RHODOSPERMEiE. [Gigartina. 



Surely very distinct from the preceding. I have received specimens 

 from the Coast of North America, near New York, precisely agreeing 

 with our Irish plant in every character. 



5. C. articulata, Hook. Articulated Chylocladia. Frond 

 tubular, membranaceo-gelatinous, strongly constricted through- 

 out as if jointed, much branched in a fasciculato-dichotomous 

 manner; branches patent; joints somewhat fusiform, much 

 attenuated at base ; " capsules urceolate." (Grev.) Hook. Br. 

 Fl. v. ii. p. 298. — Fucus articulatus. Turn. t. 106. E. Bot. 

 t. 1574. 



On rocks and the larger Algte, very common. Fronds 4 — 12 inches 

 in length, dark-red, excessively branched in a dichotomous manner, and 

 catenulato-constricted throughout. 



45. Gigartina. Lamour. Gigartina. 



Frond more or less cartilaginous, filiform, cylindrical or com- 

 pressed, irregularly branched, of a dull-red colour. Fruct. : 

 capsules containing a mass of minute roundish seeds, antl (in 

 many of the species, perhaps in all,) roundish or oblong 

 simple granules, imbedded in the fronds of distinct plants. 

 Grev. Hook. — Name, from ^i^ap-rov, a grape stone, which 

 the seeds somewhat resemble, as seen through the capsule. (!) 

 Hook. 



1. G. purpurascens, Lamour. Purplish Gigartina. Frond 

 cylindrical, filiform, bushy, excessively and very irregularly 

 branched ; ramuli setaceous, acute, scattered, containing im- 

 mersed sphaerical tubercles. Hook. Br. Fl. v. ii. p. 299. — Fu- 

 cus purpur. Turn. t. 9. E. Bot. t. 1243. — Gracilaria purp., 

 Grev. Alg. p. 122. 



Rocky shores, very common. 



2. G. confervoidcs, Lamour. Conferva-like Gigartina. Frond 

 cartilaginous, cylindrical, filiform, irregularly (often very 

 slightly) branched ; branches long, subsimple ; ramuli scat- 

 tered, attenuated at each end ; capsules external, roundish, 

 scattered. Hook. Br. FL v. ii. p. 299. — Fucus conf. Turn. 

 t. 84. E. Bot. t. 1668. — Gracilaria conf. Grev. 



Sea-shores, not rare. Bantry ; Miss Hutchins. Miltown Malbay, 

 and near Dublin ; W. H. Harvey. Black rocks, Portrush ; Mr. D. 

 Moore. 



3. G. erecta. Small upright Gigartina. Frond cylindrical, 

 dichotomous, erect ; branches subsimple ; capsules globose ; 

 granules in terminal pod-like ramuli. Hook. Br. FL v. ii. p. 300. 

 — Gracilaria erecta. Grev. Alg. Brit. p. 124. t. 14. Sphcero- 

 coccus? erectus, Grev. Crypt. Fl. t. 357. 



Sand-covered rocks. Bangor, County of Down ; TV. Thompson, 

 Esq. %.. February, March. It is slender, erect, rigid, 2 — 4 inches 



