200 ALG/E RHODOSPERMB^E. [Gigarlina. 



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. articulaia, Hook. Articulated Chylocladia. Frond 

 tubular, membranaceo-gelatinous, strongly constricted through- 

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

 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 Alga?, 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. Frucf. : 

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

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

 simple granules, imbedded in the fronds of distinct plants. 

 Grev. Hook. Name, from fytfya/JToi/, 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. confervoides, 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. \668.-Gracilaria conf. Grev. 



Sea-shores, not rare. Bantry ; Miss Hutckins. 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? ercctus, Grev. Crypt. FL t. 357. 



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

 Esq. !{. . February, March. It is slender, erect, rigid, 2 4 inches 



