10 OTTO V. DARBISHIRE. [SEC. ARCT, EXP. FRAM 
Lecidea purissima. (Tab. 4, fig. 1). 
Diagnosis: Crusta crassiuscula indistincte areolata, albida vel di- 
lutissime flavescens, partibus albidis discontiguis sed hypothallo nigro 
impositis, hypothallo nigro instructa. Apothecia usque ad 1 mm. lata, 
primum .immersa et thallo subaequantia, marginata, nigra, deinde quasi 
elevata, subsessilia convexa et immarginata; epithecium nigrum; hypo- 
thecium decolor; asci inflato-clavati; paraphyses simplices; sporae octo- 
nae, hyalinae, 12.5 mi.—15 mi. longae, 5—6 mi. latae. Habitat ad saxa. 
Notes: This species is characterised by the smaller or larger 
white portions of the thallus which are not continuous, but which are 
superimposed on an hypothallus of dark colour. Externally it much 
resembles a specimen of “Lecidea alpicola, Wau. Port Kennedy, Dr. 
Watker 20.” in the Herbarium at Kew. But this is really Catocarpon 
chionophilum, Tu. Fr., and its spores are in fact two-celled, black and 
measure 22—36  11—18 mi. Our species differs from Lecidea macro- 
carpa (DC.) Ty. Fr. by its smaller spores. I think that it is a new spe- 
cies. But as I mention later on the Lecideas of the world require re- 
vising monographically. 
Lecidea solitaria. (Tab. 1, fig. 2). 
Diagnosis: Crusta tenuissima, fere obsoleta, albida, hypothallo 
nullo distincto; Apothecia dispersa, ad 1 mm. lata, nigra, margine con- 
colori cincto, demum immarginata, convexa; epithecium nigrum; hypo- 
thecium decolor; paraphyses non-articulatae; sporae octonae, non-unise- 
riatae, subglobosae, 5 >< 6.4 mi. magnae. Habitat ad saxa. 
Notes: From the description this plant appears to be not unlike 
Lecidea ultima, Tu. Fr., but in the latter the hypothecium is darker, 
the paraphyses are articulate and the spores uniseriate. It also in some 
respects resembles the “crusta fere nulla” — forms of Lecidea auricu- 
lata, Tu. Fr. but the persistent margin of the latter is a distinguishing 
feature. 
Catillaria sanguinaria. 
Diagnosis: Crusta tenuis, cinerascens, minute rimoso-areolata, 
margine fusco-nigricanti, hypothallo albido, fere effigurato, centro rimoso- 
diffracta et fere papillosa. Apothecia minuta, ad .3 mm. lata, papillis 
immersa, nigra, margine albido cincta, convexa, lecideina; epithecium, 
parathecium et hypothecium nigrum; sporae octonae, halone nullo, 16 x 6 
mi. magnae, bicellulares, hyalinae. Habitat ad saxa. 
