18 



CARL SKOTTSBERG, MARINE ALCffi 1. PH^OPHYCE^. 



closely resembles. Still 1 am convinced that they are two distinct species: M. 

 fuegianum differs in the shape of the disc-cells, in the gametangia being more or less 

 biseriate, etc. Of European .species, it resembles M. foecundum Strömf., but this 

 seems to have shorter and thicker gametangia (35 — 40x8 — 12[x) and has no erect 

 filaments. According to Cotton, Clare Isl. Surv. p. 122, thelatter belongs to Ascocyclus. 



M. patagonicum nov. spec. — Fig. 7 n— p. 



Discus basalis cellulis sat magnis, 15—20x6 — 9^, chromatophoris 1 — 3. Fila 

 erecta nulla. Pili sat numerosi, 8 — 9[x crassi, basi angustati. Gametangia valde 

 numerosa, linearia, 30 — 60 x 8 — 10 [x, uniseriata, sessilia vel breve pedicellata. Sporangia 

 ignota. 



Fig. 8. a — d Petroderma maculiforme: a part of horizontal thallus, X 360; b erect filaments with sporangia, X 3(50; 

 C do with anomalous cells, X 3t>0 ; d two filaments with ripe sporangia, X 575; e — IU Lithoaerma pili/erum, X 300 : e — k 

 of the larger, 1 — ill of the smaller form; e horizontal thallus, f section of margin, g section of thicker part, h three 

 young hairs, i old hair, k sporangia and chromatophores, 1 horizontal thallus, 111 erect filaments and liair. 11 Balfsia 



australis, section with gametangia, X 250. 



Patagonia: Skyring Water, Pnnta Rocallosa on drifted pieces of Macro- 

 cystis, mixed with Hecatonema (29. 4. 08, gt.). — This differs largely from the pre- 

 ceding species by the form and size of the basal cells and by the larger but uniseriate 

 gametangia. In outline these resemble those of M. foecundum f. seriala. The 

 narrowed base of the hairs in the new species may offer a good character. 





