LICHENES— DK JEAN MULLER. 369 



4. P. (Raphiospora) decussata, Miill. Arg. 



Thallus tenuis et depauperatus, minute leproso-granularis, argillaceus v. albido-argillaceus, lineis 

 hypothallinis nigris laxe peragratus; gonidia globosa, 5-9 /m lata, glomerulosa. Apothecia 

 sessilia, ab origine atra, evoluta \-^ rum. lata, saepe minora, crasse et semper prominenter 

 nigro-marginata; discus planus; epithecium virenti-nigrescens, lamina circ. 80 jx alta, 

 superne virens, cseterum parte superiore bypotheeii late hyalina, hypotbecium inferne 

 fuscescens; paraphyses capillares. subliberse, tantum 1-lj mm. crassse. Asci 8-spori. 

 Sporee (hylinte) circ. 55 fx longse, 4 p. latse, aciculari-fusiformes, 10-15 loculares. 



Primo intuitu formam exiguam simulat Zecidece latypece, Nyl. 



Socotra. A saxa calcarea. B.C.S. n. 1460. 

 Distrib. Endemic. 



4. BUELLIA. 



Buellia, Mass. Eich. 80; Mull. Arg. Licb. Geneve 63. 



Buellia, De Notaris Frammenti 22 pr. p.; Tuck. Gen. 183 pr. p. 



A large genus of all countries. The number of exotic species known rapidly 

 increases, and they are predominant in the lichen-flora of Socotra. Five of 

 our nine species are endemic. 



1. B. parasema, Korb. Syst. p. 228. 



Socotra. B.C.S. n. 1354 pro parte and 1415 pro parte. Ad ramulos 

 Balsamodendri supra Wadi Digal, alt. 300 m. Schweinf. 

 Distrib. Common everywhere. 



a. var. rugulosa, Korb. Syst. p. 228. 



Socotra. Ad cortices. B.C.S. nn. 1354 pro parte, 1415 pro parte. 

 Distrib. Very common. 



b. var. subseruginascens, Mull. Arg. in Proc. Roy. Soc. Edin. xi. 

 (1882), 465. 



Tballus albicans, rugoso-areolatus ut in var. rugulosa, Korb., sed apothecia obsolete v. leviuscule 

 aeruginoso-pruinosa ut in var. ceruginascente, Mull. Arg. (Lecidea disciformi v. ceruginas- 

 cente, Nyl. Chili, p. 166). 



Socotra. Ad ramulos Balsamodendri supra Wadi Digal. Schweinf. 

 Distrib. Endemic. 



c. var. contorta, Miill. Arg. in Proc. Roy. Soc. Edin. xi. (1882), 464. 



Thallus crassus, subrugoso-areolatus, magis subdecolorato-argillaceus v. ochraceo-cinereus, 

 apotheciorum margo demum valde contortus, discus seruginascens. 



Socotra. Corticola. B.C.S. n. 1563 pro parte. 

 Distrib. Endemic. 



TRANS. ROY. SOC. EDIN. VOL. XXXI. 3 A 



