SYSTEMATIC ACCOUNT 17 



the aid of a ^^ 10 lens here and there around the thalline patches. Thallus in section with ver}^ irregular 

 upper surface bounded by a brown-blackish cortical layer 6-8 // thick with indistinct, + round cells 

 3-5 n diam. Most of the fungal tissue between the gonidial algae is also dark. Gonidia extend through- 

 out whole depth of thallus, not in vertical rows ; bright green, i globose, 5-8 (-12)// diam., thin-walled, 

 multiplying apparently by binary fission. Perithecia up to 0-2 (-0-25) mm. diam., hemispherical to 

 subglobose, black, matt or slightly shining, clothed by thallus in lower half, or in young perithecia 

 almost to the ostiole. Ostiole apical, minute, not or only slightly impressed. Excipulum i globose or 

 slightly flattened, 145-210// diam., with faintly brownish or almost colourless wall 12-30/^ thick 

 composed of compacted, tangentially running hyphae about 2 ft thick. Involucrellum overlaying 

 excipulum and extending down to its base, brown-blackish in outer half to three-quarters, paler brown 

 inside; about 30 // thick near ostiole, up to 80// thick at base, not extending below the excipulum. 

 Periphyses numerous near ostiole, ±simple, 15-24X i •5-2-0//. Paraphyses soon diffluxed and evane- 

 scent. Asci clavate, 60-65 ^' 18-21 //, with colourless gelatinous wall up to 4(-5)// thick. Spores 6-8, 

 irregularly biseriate in ascus, elongate-ellipsoid, the ends rounded or sometimes bluntly pointed, thin- 

 walled, 18-20 < 7-5-8-0//. With iodine, hymenial gelatine, and sometimes ascus walls also, pale rose- 

 pink ; contents of asci and spores yellowed. 



This species apparently belongs to the very critical group of V. aethiobola. 



Verrucaria maura Wahlenberg 



apud Acharius, 1803, suppl. p. 19; Vainio, 1903, p. 38; Zschacke, 1934, p. 179. 



Not present in our collections ; the only antarctic record is that of Vainio, from west Graham Land : 

 Palmer Archipelago, Moreno Island. 



Geographical Distribution. A widespread species, occurring on the coasts of Europe, North 

 America, Greenland, Iceland, Spitsbergen, Bear Island, Novaya Zemlya, Siberia, Bering Strait, 

 Japan, and, in the southern hemisphere, Fuegia, Patagonia, South Chile, Falkland Islands^ and New 

 Zealand. 



Verrucaria microspora Nylander (Fig. 3 A) 

 1855. P- 175; Zschacke, 1934, p. 195. 

 Verrucaria microspora f. halophila Nylander, 1855, p. 175. 

 Verrucaria halophila Nylander, apud Branth and Rostrup, 1869, p. 275. 

 West Graham Land. Mainland Coast: Cape Renard; on non-calcareous rocks at about normal 

 high-tide level, constantly drenched by wave action during rough weather, together with V. mucosa 

 Wbg. ; F.I.D.S., 22. iii. 1944 (no. iijzpr.p.). Palmer Archipelago: Port Lockroy, Goudier Islet; south 

 side of islet on granodiorite rocks intermittently submerged by the tide; F.I.D.S., 23. iv. 1944 

 (no. 1220 pr. p.); east side of islet, on lower part of basalt dyke exposed only at low tide; F.I.D.S., 

 23. iv. 1944 (no. 1228). 



South Orkneys. Fredriksen Island: on non-calcareous rock; Discovery 193 1-3, 4. i- 1933 ("os. 1090 

 -19, 1090-28). 



Sporadic and scarce. F.I.D.S. no. 1228 is the typical form, with entirely colourless excipulum; the 

 other specimens belong to the iorm frisiaca (Erichs.) Santesson, 1939, p. 41 (V. frisiaca Erichsen, 

 1930, p. 224), characterized by the somewhat pigmented, brownish excipular wall. Spores 8-12 

 X4-5//. 



Geographical Distribution. New to the Antarctic; widely distributed on the coasts of Europe, 

 also recorded from North America (Maine), Greenland, Japan, and Chile. 



1 Collected by me at Port Louis, Berkeley Sound, in Feb. 1946. 



