1898—1902. No. 21.] LICHENS. 11 
Notes: This new species is characterised by a thin but distinctly 
areolate and greyish thallus and a very clearly marked hypothallus of 
a darkish colour, which ist almost effigurate at the margin. It thus 
differs from Catillaria subalpina, Tu. Fr. (Lich. Scand. p. 583). The 
size of the spores and the structure of the apothecium are also typical 
features. 
Catocarpon depressum. (Tab. 1, fig. 3). 
Diagnosis: Crusta tenuis, vel crassior, continua, partim albo- 
coerulescens et rimoso-areolata, partim albida vel dilutissime rubescens 
et effusa, hypothallo mgro. Apothecia ad 1.5 mm. lata, primum im- 
mersa, margine distincto cincta pallido, demum erumpentia et elevata, 
immarginata, convexa, nigra; epithecium, parathecium et hypothecium 
nigrum; sporae octonae, hyalinae, bicellulares, halone distincto circum- 
datae, 15—16  7—8 mi. magnae (halone non incluso). Habitat ad saxa. 
Notes: This is a very distinct species, and it appears new. It 
resembles Catocarpon chioneuin (Norm.) Tu. Fr., but it differs atleast 
in having a distinct hypothallus, in the apothecia not being flat, and 
not having a thickish margin, and in the spores being bigger than is 
the case with C. chioneum. 
Pertusaria determinanda. (Tab. 2, fig. 1). 
Diagnosis: Crusta .5 ad 1.0 mm. crassa, rimoso-areolata, albella 
vel roseola; verrucae fertiles irregulariter globosae, ad 1.5 mm. latae et 
ad 1.2 mm. altae, apicibus depressae, ostiolis apotheciorum usque ad 10, 
punctiformibus, fuscescentibus instructae; sporae octonae, elongatae, 26— 
30 X 8—10 mi. magnae. Habitat ad saxa. 
Notes: This new Pertusaria differs from Pertusaria rhodoleuca, 
Tu. Fr. (Lich. Scand. p. 306) and P. wanthostoma by its smaller and 
octone spores. It also resembles P. pocillaria, Cummines (Alaskan Lich- 
ens p. 101, pl. 9) but the spores of the latter are much larger. 
Placodium splendens. 
Diagnosis: Crusta adpressa, quasi foliacea, dense squamulosa, et 
adscendens, aurantiaca. K + intense purpurascens, infra rhizinis destituta 
et colore albida, utrinque corticata, strato corticali plectenchymatico di- 
stincto, supra et infra ad 30 mi. crasso. Apothecia ad 2.5 mm. lata, 
concoloria, lecanorina, primum margine cincta distincto, demum sine mar- 
gine distincte viso, plana; sporae octonae, polari-dyblastae, apicibus ro- 
