l6 OTTO VERNON DARBISHIRE, (Schwed. Siidpolar-Exp. 



thallus bene evolutus, albissimus, ex hyphis formatus tenuissimis, ex margine thalli 

 ortus nigricanti; apothecia nigra, emergentia, semper convexa et margine proprio 

 destituta, 0.5 — 1.5 mm lata; epithecium, parathecium et hypothecium carbonaceum; 

 sporae octonae, fuscae, aut parce viride-fuscescentes, bicellulares, medio non constrictae, 

 12 — 18x6 — 9 // magnae; spermogonia non visa; habitat ad saxa, Graham Land, 

 Paulet Island. 



Notes: The most noticeable feature about this plant is the remarkable hypo- 

 thallus of a very clear white colour which separates it very distinctly from the black 

 margin of the thallus which is at this point as thick as further in towards the centre 

 of the whole plant. Quite up to the black margin the thallus is areolate and fur- 

 ther in it is so much broken up as to be almost not continuous. It occurs on very 

 rough stones and this may account for it being very uneven on the surface. 



Acarospora convoluta nov. spec. 



(Plate 3, fig. 32). 



Thallus crassus ad 5 mm, multo convolutus et intricatus, et quasi fruticulosus, 

 cinerascens aut pallide lutescens; K — ; apothecia primo immersa dein emergentia 

 paulo, lecanorina, 1 — 1.5 mm lata; epithecium rufescens; amphithecium marginem 

 thallodem faciens crassum thallo concolorem; discus primo planus dum convexus; pa- 

 rathecium et hypothecium hyalinum; asci polyspori; sporae hyalinae, unicellulares, 

 4 — 5x2 — 2.5 fi magnae; spermogonia nulla visa; habitat ad saxa, Graham Land, 

 Louis Philippe Penins., Astrolabe Island. 



Notes: This species is noticeable on account of the well marked development 

 of the thallus which almost takes the form of small fruticulose podetia. It is almost 

 impossible to speak of a crustaceous thallus. The apothecia show no important 

 features. 



Parmeliella minor nov. spec. 



(Plate 3, fig. 31.) 



Thallus squamulosus, adpressus, squamis constans vulgo 1 mm rarius ad 2 mm 

 latis et margine crenulatis, castaneus, sed marginem pallidior et quasi pruinosus, 

 superne glaber, bene corticatus, inferne ecorticatus, rhizinis et hypothallo pannarioideo 

 substrato affixus ex hyphis constante nigricantibus; gonidia nostocacea; apothecia 

 urceolata, biatorina, emergentia et quasi stipitata et mox basi parce constricta, 0.5 — I 

 mm lata; parathecium bene evolutum et marginem proprium formans crassum et 

 crenulatum, thallo concolor; epithecium rufescens, planum et dein parce convexum; 

 hypothecium pallidum et parathecium interne pallidum; sporae octonae, polyseriatim 

 dispositae, hyalinae, unicellulares. 20 — 22x16 — 18 /( magnae; spermogonia nulla visa; 

 habitat ad corticem arborum. Tierra del Fitego, Harberton. 



