COLLECTED JN THE ISLAND OF RODRIGUEZ. 443 



oblougae, simplices, Ion git. (MM 1-0014 millim., crassit. 0004-0005 

 millim. ; paraphyses graciles ; epithecium sublutescens aut dilute 

 glauco-fuseescens ; hypothecium incolor. Iodo gelatina hymenialis 

 caerulescens, dein violascens. 



44 E stirpe Lecidem Icevigatce species, simplex, facie fere Lecidece ph&opis. 



Thallus K flavens." — NyL in lift. 

 On rocks ; sparingly gathered. Coll. Balf. no. 2224. 



Tribe Gbapiiidei. 



Opegrapha difficilior, NyL, sp. n. 



44 Thallus macula albescente indeterminate vel obsoleta indicatus ; apo- 

 thecia nigra linearia (longit. 1-2 milliui. vel breviora, crassit. fere0 # 25 

 millim.), subsimplicia, recta aut subflexuosa, superficial ; epithecium 

 rimiforme demum arete angustatum ; sporse 8nae, fusiformes (vetus- 

 tate obscuratae), 5-7-septatic, longit. (M)27-0*033 millim., crassit. 

 0004-0006 millim., hypothecium nigricans. Iodo gelatina hyme- 

 nialis vinose rubens. 



44 Sat affinis Opegrapha hapaleoidi, sed thallo, apotheciis ct sporis diffe- 



rens. Apothecia ssepiua conferta. Spernjatia tenuia, rectiuscula, longit. 



0* 004-0 005 millim., crassit. 0*0005 millim, Comparanda, quoad 



faciem, cum O. difficili, Duf. (quae non est nisi O. cinerea, Chev. ! 



lignicola), spermatiis aliis uiox diveraens." — NyL in litt. 



On decorticated stumps of trees ; sparingly gathered. Coll. Balf. no. 

 2251. 



Arthonia phylloica, Nyl. 9 sp. n. 



"'Thallus macula alba indicatus; apothecia nigra tenuia erumpentia 

 linearia (longit. 1 millim. vel nonnihil longiora aut breviora, latit. 

 parum 1 millim. excedentia), simpliciuscula aut ramulum unum alter- 

 umve emittentia, variantia subastroidea ; sporae 8nae, incolores, ob- 

 longae, 3-scptatae, minute, longit. circiter 0011 millim., crassit. 

 0*003-0004 millim.; epithecium subcaerulescens. Iodo gelatina hy- 

 menialis vinose rubens (praecedeute caerulescentia)." — Nyl. in litt. 



On thin stems ; sparingly gathered ; Coll. Balf. no. 2226. 



A. dendritella, NyL, sp. n. 



" Thallus macula albo-cinerascente subdeterminata indicatus ; apothecia 



nigricantia, tenuia, innata (latit. 01 millim. vel tenuiora), subdeu- 

 dritico-divisa aut simpliciora, sat conferta ; spone 6-8me, incolores, 

 oviform i-oblongae, 3-septatae, longit 0010-0 014 millim., crassit. 

 0004-0005 millim.; epithecium ca^rulescenti-nigrest ens; hypothecium 

 incolor. Iodo gelatina hymenialis subineolor et thecae vinose violas- 



centes. 



Species e stirpe Arthronia palmicolxe, praecipue facie uebuloso-petricola 

 et reactione iodo effecta distincta/' — Nyl. in litt. 

 On thin bark of trees ; sparingly gathered. Coll. Balf no. 2300. 



