6 AUSTRALASIAN ANTARCTIC EXPEDITION. 



rocks, while P. crispa is rarely found to occur on rocks. The specific distinction seems 

 rather trivial, while the difference in habit is perhaps simply due to the fact that if the 

 plant is to grow in Antarctica at all, it must be on rocks or in their crevices. There is 

 no soil proper for them to grow on. P. crispa in Europe specially affects moist bare 

 ground impregnated with urine and old thatched roofs. Its appearance in Antarctica 

 on guano seems, therefore, perfectly natural. 



Dr. L. Gain in Deuxieme Expedition Antarctique Franchise, La Flore Algologique, 

 considers P. aiitarctica as a synonym of P. crispa. 



(Plate 8, fig. 3, 4.) 



Distribution. — Widely distributed over Europe and North America, and occurring 

 in the Arctic regions. 



In the Southern Seas it has been recorded from the Falkland, South Orkneys, 

 Cockburn I., and was obtained by the Borchgrevink and Shackelton Expeditions from 

 Victoria Land. 



Dr. L. Gain (l.c.p. 178), writes of it— " Abondant dans la region parcourue par 

 le ' Pourquoi-Pas ? ' On le rencontre surtout dans les parties basses, sur les petites 

 iles, sur les rochers, pres des Mousses, aux endroits humides ou coule l'eau provenant 

 de la fonte des neiges." — Port Lockroy (ile Wiencke ) Dec, iles Booth- Wandel, Petermann, 

 Argentine, Jenny, Leonie, Terre de Graham, January to March. 



Somewhat extended investigation failed to reveal any other algse growing with 

 the Prasiola. Nothing definite was observed beyond a limited number of species of 

 Infusoria, barbules of penguin feathers and bacteria. 



Cladophoraceje (Hassall) Wittrock. 



Chcctomorpha Kuetzing. 



Chcetomorpha Mawsoni, sp. nov. 



Species halophila. Filamentis flaccidis, gregariis, separate adfixis conico basali 

 disco, ad 26 cm. longis : articulis e basi sensim incrassatis ; inferioribus cylindraceis, 

 haud ad septa constrictis, diam. 92ju. ; intermediis ovalibus, ad septa coDstrictis, 

 diametro 3 plo longioribus, e.g., 400 x 139/x; superioribus sensim magis inflatis, pro 

 ratione latioribus, e.g.,' 570 x 276/x, dein 2,000 x 1,078/a, supremis 2,000 x 1,333^: 

 membrana conspicua; colore (formalin) sordide viridi. 



Filaments flaccid, growing together in great numbers, but each provided with a 

 separate conical disc for attachment, and expanding very gradually from base to apex, 

 attaining a length of as much as 26 cm. 



Disc conical, diameter of base 293/a. 



