366 BOTANY OF SOCOTRA. 



1. B. poliotera, Miill. Arg. Lich. Afr. Occ. n. 23. 



Lecanora poliotera, Nyl. Lich. Kurz. Beng. n. 3. 



Soeotra. B.C.S. n. 1380 (specimina manca). In adscensu septentrionali 

 montis Bagne, alt. 500 m. Schweinf. 

 Distrib. Angola, East Indies. 



2. B. albido-cserulescens, MUU. Arg. in Proc. Roy. Soc. Edin. xi 

 (1880), 462. 



Thallus cinereo-albidus, tenuis, distincte aut discreto-areolatus, areolae angulosae, plana? et 

 subpolito-laevigatae, in hypothallo caerulescente sparsae et subcontiguae et secus margines 

 subcaeruleo-tinctae, caeterum paucirimosae. Apothecia vix £ mm. lata, sessilia planiuscula, 

 nigro-inarginata, discus rufus v. ferrugineo-fuscus; sporae 4-8-nae, 11-13 /x longae, 6-7 /x lata?. 



Proxima est B. poliotera;, Miill. Arg. et B. variabili, Miill. Arg., priori tamen affinior, sed thallus 

 multo tenuior et laevigatus, albidior, non plumbeo-cinereus, areolae plana? et hypothallus 

 valde evolutus. Discus longe intensius rufesceus quam in posteriori, cujus thallus tantum 

 rimulosus v. rimosus, nee vere areolatus est. 



Soeotra Ad saxa quartzosa. B.C.S. n. 1439 pro parte. 

 Distrib. Endemic. 



3. B. cretacea, Mull. Arg. in Proc. Roy. Soc. Edin. xi. (1882), 462. 



Thallus cretaceo-albus, farinulentus, tenuis, continuus, demurn tenuiter rimulosus et corroso- 

 rarescens, margine linea caeruleo-nigricante ductus ; apothecia £— £ mm. lata, sessilia, 

 saepius prominenter marginata, margo integer et niger, tenuis, discus planus, rufo-nigricans , 

 v. obscure ferrugineo-fuscus, demum nigrescens, nudus ; epithecium caerulescens v. violaceo- 

 nigricans; hypothecium cum lamina hyalinum. Sporae (orculi formes) 9-10 /j. longae, 5-6 /x 

 latae. 



Juxta aegyptiacam B. melanocarpam, Miill. Arg. locanda. 



Soeotra. Ad saxa calcarea. B.C.S. n. 1409 pro parte. 

 Distrib. Endemic. 



4. B. variabilis, Mull. Arg. in Proc. Roy. Soc. Edin. xi. (1882), 462. 



Thallus subilavescenti-cinereus, tenuiusculus, demum continuus et laevis, margine sublavato- 

 effusus, et nihilominus bine inde zona cseruleo-nigrescente cinctus, dein sensim paullo 

 crassior et tenuiter rimulosus demumque magis albicans. Apothecia adnato-sessilia, 

 primum laete fulva et margine crasso concolore cincta, mox fuscescentia et tunc margine 

 nigrescente tenuiore praedita, demum fusca, v. nigrescenti-fusca eb tenuissime nigro- 

 marginata, |-J- mm. lata ; epithecium late fulvum, lamina cum hypothecio hyalina. 

 Sporas (orculiformes) 12-14 /x longae, 6-8 fx latae. 



Status junior quoad thalluin fere cum B. peragrata (Lecanora peragrata, Krplh. Lich. Glaz. p. 

 22), conveuit, plaue evolutu3 magis ad B. polioteram, Miill. Arg. accedit, cujus thallus aliter 

 coloratus et areolatus est. . 



