8 CARL SKOTTSBERG, MARINE ALG^ 2. RHODOPHYCE^E. 



I. dichotoma Hook. Fil. et Harv. Lond. Journ. Bot. 4 (1845) p. 262. 



Syn. /. cordata y dichotoma Hook. Fil. et Harv. Fl. Ant. II, p. 485, p. p. /. 

 dentata Kutz. [3 minor Sp. Alg. p. 729. 



South Patagonia: Fitzroy Channel, 13 — 14 m, on Mytilus (St. 17, 18.4. 

 08). Falkland Islands: Low Bay on Mytilus (St, 18 B, 18. 1. 08); Westpoint 

 Island, in tide-pools (St. 8 a, 5. 12.07); Cape Pembroke, upper litoral basins (St, 3 b, 

 7. 11.07, ?). 





Fig. 1. a = Gelidium crispum, X 3. b Iridaea macrodonta, f nat size. C Gigartina glomerata, X 1 i- 



Hooker and Harvey are not sure whether there be any exact limits between 

 this form and /. micans. It comes nearer to /. laminarioides, but the habit is so different 

 that I prefer to keep them distinct. The cystocarps are more protruding than in other 

 species from the south. Hooker' s type material, which I have seen, includes specimens 

 rather referable to cordata. 



Distribution: S. Patag. (first record), Falkl. 



I. macrodonta nov. spec. — Fig. 1 b. 



Frondes plurimae e disco basali minuto caespitosae, breviter stipitatae; lamina 

 molliter membranacea, suborbicularis, in speciminibus nostris circ. 11 cm longa ac lata, 

 integra sed margine circumcirca grosse dentato-lobata, dentibus aliis majoribus usque 



