4 M. FOSI.IE, (Schvved. Siidpol:iv-E.\p. 



of L. Pateiiû, but less regular in form and more adnate". J. G. Agardh has dis- 

 tributed an intermediate form from Southern New Zealand, labelled ^^ Melobesia ant- 

 arcticar Vix nisi var. Melob. Pntcnœ". This form stands in habit between L. ant- 

 arcticnm and L. Patena. and the conceptacles are rather densely crowded in the central 

 parts of the frond, as in the latter, but smaller than is usually the case in this alga. 

 As to structure the hypothallic cells are narrower than frequently is the case in L. 

 Patena. By the bye, as to the statement of Heydricii, 1. c. p. 543, that the con- 

 ceptacles of sporangia of L. Patena are i — 1.2 mm. in diameter, this is in so far a 

 misstatement as they are generally onl\- 0.7 (o.e) — i mm. in diameter, while in the type 

 specimen of Litliotli. aiitarcticuni they are 0.5 — 0.7 mm. in diameter. In L. Patena 

 f. incisa, which is sometimes loosely attached to the host by its whole lower side, 

 the conceptacles of sporangia are 0.5 — 0.8 (0.9) mm. in diameter. On the other hand, 

 there is no definite line between L. Patena and L. lichenoides. Thus I have seen 

 specimens of the latter from the Mediterranean both in habit and in the size and 

 the shape of the conceptacles almost corresponding with typical L. Patena. Both 

 the said alga;, however, are, as a general rule, somewhat diverging, even apart from 

 coarse and prolific forms of L. liclienoides which are considerabh" distinguished from 

 L. Patena. Therefore, it ma\ be most reasonable to consider the three alga; as in- 

 dependent species. 



In the collection in hand there is only a single specimen of Ballia from the 

 Falkland Islands to which small fronds of the species in question are attached, picked 

 up at Port V\"illiams from a depth of 22 fathoms. They were partly provided with 

 mature sporangia at the beginning of July. 



Area: Fuegia: Hermite Island, Cape Horn (HooKER) and near the mouth of 

 Rio Grande (DusLN); the Falkland Islands (sec. Harvey, Skott.sberg); South 

 Orkneys ("Scotia")?; ' Kerguelen (H00KER, EATON, "Gazelle"-Exp.); Tasmania, 

 Auckland (sec. Dickie). 



2. Lithothamnion magellanicum Fosl. 



New or crit. Lithoth. (1895), p. 8, fig. S. 

 f. tvpica. 



Tab. nostr. 1, fig. i — 3. 

 f. crenulata FOSL. 



New or rrit. Lithoth. I. c: Hohnes, Some South. Orkn. Algae in Jouni. of Bot. 1Q05, 

 p. i9<S. 



The typical form of the species is mostly attached to mollusc shells, sometimes 

 to other calcareous algae or to stones. The crust is smooth and faintly shining, 



' Holmes, Some South (Irliney Alga' [Journal of Kotaiiy XLIII (1905) p. 197] admit* the species 

 from the South Orkneys, but with a query added. I have seen no specimen from this place. 



