LICHENS AND FUNGI OF OTAGO, NEW ZEALAND. 419 



thallus varies from pale grey to lurid (blackish-brown). The minutely squamulose 

 character of the thallus gives the plant the aspect of a P armaria. The hymenium 

 and thecse give a beautiful blue with iodine. The latter are 8-spored (with the 

 spores generally arranged in a single series), -0036" long, and -0006'' broad. The 

 sub-discrete, filiform paraphyses are united by yellow clavate heads. The spores 

 (fig. 30) are broadly ellipsoid, oval or oblong ; simple, colourless ; with double 

 contour generally in the mature state (a) ; -0006" long, and -00045" broad. What 

 appear to be spermogones are marginal, brown tubercles, resembling the spermo- 

 gones of Peltigera and Nephroma, containing myriads of atomic or ellipsoid sper- 

 matia (fig. 31), about -0001" long, and -00005" broad; possessed of vivid Brownian 

 movements, borne apparently on arthosterigmata, which are indistinct. 



The species is confined to warm countries, such as South America and Australia. 

 In specimens in the Hookerian Herbarium, from the Cape (Miller) and the 

 Mauritius, I found the spores of the same character as those in my Otago plants, 

 differing only as to size, being here -00038" long, and -00020" broad. 



Var. plwlidotoide, Nyl., Lich. N.Z., 250. 



[ On living trees, East Taeri, and Saddlehill, Bush. 

 The thallus is rudimentary, consisting of a few minute, sparsely scattered 

 scales, seated on the black hypothallus, the plant having thus the aspect of cer- 

 tain of the smaller Endocarpa. The apothecia are large, closely crowded in the 

 centre of the thallus, almost constituting the plant ; becoming, from mutual pres- 

 sure, irregular and difform, sometimes sub-confluent. They have a thickish, rugose 

 or crenulate thalline maVgin, and a disk of chestnut colour, without any tinge of 

 black. This form frequently bears considerable resemblance to various Pannaria?, 

 e.g., P. brunnea, Sw., or P. nebulosa, Hffm. Its thecse and spores are exactly 

 those of the type. 



26. Physcia plintluza, Nyl., Licb. N.Z., 249 (fig. 32). 



On the trunks of living trees, Greenisland Bush ; bearing both apothecia 

 and spermogones. 



The thallus is distinct and foliaceous ; sometimes lobulate, of a slate-grey 

 colour, apt to be obscured by overgrowing Jungermannise. The apothecia become 

 with age convex, and have a widened, flattened exciple. The hymenium, thecse, 

 and tips of the paraphyses all assume a more or less deep and beautiful blue 

 with iodine; this tinge is sometimes comparatively deep on the tips of the 

 paraphyses, while it is very pale on the apices of the thecse. The thecce are 

 8-spored, -0036" long, and -0009" broad. The spores (fig. 32) vary considerably in 

 their characters, combining the features of those of Verrucaria nitida and Physcia 

 puherulenta. Their usual length is from 0009" to -00135", breadth about 00045"; 

 their general form broadly ellipsoid or ellipsoid-oblong. Sometimes they are 



VOL. XXIV. PART II. 5 X 



