PHYSC1A. 



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the Archipelago into Alexandria : a handful was steeped for 

 two hours in water, and the infusion added to the bread. 

 "We have found it yield, on ammoniacal maceration, a fine 

 orchill. From the capacity of its powder to absorb and re- 

 tain odours, it was long greatly used in perfumery. 



4. Physcia chrysophthalma (^pucro?, gold, and 6cf)daX- 

 fios, the eye) . Lacinise, — above yellowish or orange, — below 

 white, lacunose, — linear, ascending, dichotomously ramose ; 

 extremities dilacerate or ciliate; apothecium varies in site; 

 thalamium orange ; margin thin, naked, or ciliate-radiate. 



A very beautiful corticolous species, growing in the form 

 of a small fruticulose tuft. In Britain it is a very rare 

 species; we have seen specimens in abundant and fine 

 fructification from Switzerland. Its thecse and spores re- 

 semble those of Parmelia parietina. 



P. intricata and P. leucomelas (Xeu/eosr, white, and /neXas, 

 black) (E. B. 2548) are also very rare in Britain, occurring 

 only in a few localities. The former differs from P. ciliaris 

 in its lacinise being naked at the margins, the thalamium of 

 the apothecium not pruinose, and its margin very entire. 

 The latter more closely resembles the same species, but the 

 lacinise are narrow and ascending, and the cilia or marginal 

 fibres very long, black, and tomentose. 



