96 



dullahyphsecrass8e,superliciei parallela3 rainosasque. 

 Apolhecia cupuiiformia. Spotœ hyalinœ, angustse, 

 simplices aut uniseptatse. Spermcgonia ignota. 



Ex eo quod Ihallus sit foliaceus et hyphge corticis 

 decompositse, locum systematicum oblinere débet 

 illa parva tribus prope Parmeliearum tribum in 

 cujus plerisque speciebus cortex superior eodem 

 modo constituitur. 



Genus IV. — PHYSGIDIA ïuck. 



Observ. NorlhAmeric. and other Lich., in Proceed. 

 arueric. Acad. arts and ic/c'/ic.,1862, p. 399, et Gêner. 

 Lich., p. 43, atqae Zahlbr., Ascolich., p. 209, apud 

 Engler uud Prantl, Nalûrl. P flanzenfainil ; Parme- 

 Hopsis, subgenus Psoromopsis Nyl. St/nops. Lich., 

 Il, p. 56 et apud Hue Lich. exoL, n. 764, in Nouv. 

 Arch. Mus., 3« sér., t. 11,1890; Parmeliopsis Nyl. 

 De react. in Evern. et Parmeliops., in Flura 18G9, 

 p. 445. 



Thallus flavicans vel albidus, adnatus vel pro- 

 cumbens, parum late laciniatus aut squamulosus. 

 Cortex superior ex hyphis decompositis reteque 

 efficientibus compositus. Gonidia viridia, protococ- 

 coidea, in strato sub cortice vigentia ac interdum 

 in hune ascendentia. Medulia ex liyphis superficiel 

 parallells et ramosls constans. Cortex inferior defi- 

 ciens; subtus fibrilte albse, intricatœ stratumque 

 paulum crassum formantes, Apothecia supra thallum 

 sparsa, cupuiiformia et sessllia. Exclpull cortex 

 eodem modo ac thalll cortex compositus; perithe- 

 cium incoloratum vel brunneum et bene evolutum ; 



