372 BOTANY OF SOCOTRA. 



Socotra. Saxicola supra Wadi Kischen, alt. 600 m. Schweinf. 

 Distrib. Endemic. 



8. B. recepta, Miill. Arg. Lich. Afric. occid. n. 25. 



Lecidea recepta, Krplh. Lich. Glaz, p. 46. 



Socotra. Ad saxa quartzosa. B.C.S. n. 1373 pro 'parte. 

 Distrib. Angola, and near Rio Janeiro. 



9. B. africana, Mull. Arg. L. B. n. 123. 



Socotra. Ad saxa quartzosa. B.C.S. n. 1351 pro parte, 1438. 

 Distrib. Recently found in New Granada and Brazil. 



Tribe 10. Graphide^. 



Grapliidecc (thallo crustaceo, gonidiis chroolepoideis, apotheciis gymnocarpicis [vulgo lirellinis]). 

 Graphideee, Eschw. Bras. 55 (addit. geuerib.) ; Stitzb. Beitr. 151 pr. p. 

 Graphidei, Nyl. Essai 187 (addit. gen. ol. Lecanor.). 



The most numerous and most difficult tribe of tropical and subtropical 

 Lichens, which is also represented in temperate and colder regions by a 

 moderately large series of species, some of which are very widely dispersed. 



This group was formerly not exactly circumscribed by absolute characters. 

 The apothecia are generally lirelline, elongated, often branched, but a good 

 many species have nearly or quite orbicular lirellse, not distinguishable from 

 the apothecia of Lecidea or Buellia, and it also happens that in some true 

 Lecidea?, for instance in our Buellia parasema v. oblongata, the apothecia become 

 distinctly elongated, thus depriving Graphideoe of its otherwise peculiar and 

 universal tribal character. 



1. DIRINA. 



Dirina, El. Fries Syst. Orb. Veg. 244 ; Nyl. Essai 180 ; Tuck. Gen. 130. 

 Lecanice sect. Dirina, Stitzb. Beitr. 170. 



A small genus of temperate and warmer regions, having quite the habitus of 

 a Lecanora (and of such Platygraphas as are provided with orbicular apothecia), 

 but distinct by the structure of the gonidia. 



1. D. Ceratonise, Fries Lich. Europ. p. 194. 



Jam antea in Flora Ratisb. 1879, Lich. Beitr. n. Ill, monui hoc genus a Lecanoreis separandum 

 et propter gonidia cbroolepoideo-concatenata Graphideis esse adscribendum, ubi juxta 

 proximain Platygrapham inserendum est et a qua non differt nisi prsesentia marginis 

 proprii lecideini intra marginem tballinum. 



