176 BEV. J, M. CROMBIE ON LICHENS 



opacus, tenuis, areolato-rimosus, superficie passim obsolete albido- 

 reticulatus ; apothecia nigricantia innata, demum supra pertusa (non 

 actinostoma) ; sporae incolores (vel vetustate infuscatae), murali-divisae, 

 ellipsoideae, longit. 0'018-0022 millim., crassit. 0009-0010 millim. ; 

 perithecium cum hypothecio infuscatum. Iodo gelatina hymenialis 

 non tincta. Spermogonia sterigmatibus longiusculis ramosis generis 

 et spennatiis tenuiter fusiformi-oblongis (bacillaribus), longit. fere 

 0*004 millim., crassit. vix 0*0001 millim. 



This species is very easily distinguished by the colour of the 



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thallus and the thelotremoid apothecia. The thallus affords no 

 reaction, either with K, CaCl, or with I. IT. stictica, Krb., ap- 

 proaches less to it than U. deuteria. 



On rocks ; very sparingly gathered. 



Tribe LecidieI. 



Lecidea chlorophjiata, NyL, sp. n. Thallus cinereo-virescezis, 

 tenuiter granulosus, sat tenuis, indeterminatus ; apothecia fusca vel 

 rufescenti-fusca (lat. 0*5-0'9 millim.), juniora plana marginata, demum 

 convexa et saepe plura minora aggregata vel botryoideo-conglomerata, 

 intus albida ; sporae aciculares reetae vel rectiusculae, tenues, indistincte 

 3-5-septat«, longit. 0060-0-075 millim., crassit. 00015-0-0025 mil- 

 lim. ; paraphyses graciles : epithecium dilute subcaerulescens, hypo- 

 thecium supra rufescens et ceteroquin incolor. Iodo gelatina hyme- 

 nialis vinose rubens. 



The thallus is minutely cellulose. With reference to the spe- 

 cific name, Nylander observes, " Acceptum est in lingua Latina 

 nomen adjectivum leucophceatus, quamobrem etiam chloropJiceatus 

 regulariter admitti possit. 



On rocks ; sparingly gathered. 



L. suBALBiCANS,NyZ., sp. n. Thallus albidus, subopacus, tenuis, minute 



areolato-diffractus, subrugulosus (K+, flavescens); apothecia fusces- 

 centia planiuscula, demum convexa (latit. 0*5 millim. vel minora), 

 margine (saepius pallescente vel albido) vix prominulo ; sporae 8nae, 

 ellipsoideae, longit. 0-009-0-011 millim., crassit. 0-005-0-006 millim. ; 

 paraphyses gracilescentes non bene discretae; epithecium subsmarag- 

 descens; hypothecium incolor. Iodo gelatina hymenialis caerulescens. 

 Spermatia arcuata (rite evoluta forsan non visa, sed videntur longit. 

 0-012-0-016 millim., crassit. 0-0005 millim.). 



This species approaches, as it seems, to L. albicans, Nyl., from 

 India; but this latter has the thallus continuous, only riniose, the 

 apothecia pale reddish, &c. Though lecanorine in appearance, the 

 apothecia are entirely biatorine. 



On rocks ; apparently not uncommon, though rarely fertile. 



