Roccella] i. discolichenes (Wainio). 433 



aut parce curvatge. Thallus rigidus, vulgo teres, 1 ad 0'7 mm. crassus. 

 Medulla jodo cserulescens. 



R. Guyana Mont. (Darb., I.e., p. 40) medulla jodo baud caerulescente 

 (thallus neque KHO nee CaCloO^ reagens) a R. hypomecha differt. 



4. R. tubereulata Wain., sp. n. 



R. Canariensis Darb., Men. Eocc. p. 50 pr. p. (specimina 

 .sorediosa). 



Thallus rigidus, long. 30 ad 80 mm., basin versus crass. 3 ad 

 0"7 mm., livido-albescens, pallescens aut fuscescens, epruinosus, 

 soraliis tuberculiformibus aut saltern margine elevatis instructus, 

 neque KHO, nee CaCl202 reagens, dichotome repetito-ramosus, 

 ramis teretibus. Medulla alba, jodo leviter cserulescens. 



Ins. Capitis Viridis. — Ad rupes in insula Fogo leg. Pharmacop> 

 Torres. No. 419. Ster. 



Var. Vineentina Wain. 



Thallo passim leviter pruinoso et soraliis CaCl202 rubentibus a 

 R. tubereulata differt, at for.san non est autonoma species. Cete- 

 rum thallus neque KHO nee CaOlgOo reagens. Medvilla alba, 

 jodo ca^rulescens. Soralia elevatfS. 



Ins. Capitis Vikidis. — Hinc inde ad rupes maritimas insulae S^ 

 Vincentii. No. 402 pr. p. 



5. R, Mossamedana Wain., sp. n. 



Thallus livido-pallescens aut albidus, soraliis cinereis, baud aut 

 vix elevatis instructus, KHO rubescens, CaCl202 non reagens, 

 rigidus, long. circ. 25 ad 30 mm., basin versus crass, circ. 05 ad 

 0"7 mm., crebi-e dichotome repetito-ramosus, ramis teretibus. 

 Medulla alba, jodo baud reagens. 



MossAMF.DES. — Ad rupes in summis jugis Serra de Montes Negros. 

 No. 418. Ster. 



6. R. Arnold! Wain. 



R. tinctoria Darb., I.e., p. 32 pr. p. (specimina sorediosa) ; Arn., 

 Lich. Exs. n. 1689. 



Thallus rigidus, ramis teretiusculis, passim levissime pruinosus, 

 sorediosus, glaucescens aut fuscescens, KHO non reagens, CaCl202- 

 rubescens, etiam soralia CaCUOo rubescentia. Medulla basis et 

 placentae alba, jodo cserulescens. Habitu similis est R. fucoicU 

 (Dicks.) Wain. {Lichen fucoides Dicks., Crypt. Fasc. ii. 1790, 

 p. 22, secund. specim. authent. in herb. Ach. ad R. phycojysin 

 Darb. vel R. phycopsin Ach., Lich. Univ. 1810, p. 440 pr. p., 

 spectat), at colore medullas placentae ab ea differt, reactionibus, 

 KHO, CaCLOo et jodo productis, cum ea congruens. In R. difficili 

 Darb., I.e., p. 49, thallus KHO non reagens, CaCl202 leviter 

 I'ubescens, soralia CaCl202 non reagentia, medulla jodo caerulescens. 

 In R. Carlbcea Darb., I.e., p. 53, thallus neque KHO nee GaCLO^ 

 reagens, .soralia CaCl202 rubescentia, medulla jodo caerulescens. 

 R. Arnoldi tantum sterilis est cognita, at saltern thallo soredioso 

 a R. tinctoria differt. In Roccellis, sicut in speciebus plurimis 

 lichenum, praesentia et absentia soralium nota est valde constans. 



