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POPULAR HISTORY OP LICHENS. 



Genus II. YEKRUCARIA, Per*. 



Gen. Char. Perithecia solitary, horny-carbonaceous, black ; 

 ostiole simple, papillseform or perforated. 



Corticolous species. 

 t Perithecium entire. 



1. Verrucaria nitida {niteo y to look bright or shining). 

 Thallus membranaceous-cartilaginous, contiguous, determi- 

 nate, olive-coloured, shining. Apothecia largish, but vary- 

 ing in size ; base innate in hemispherico-concoid, thalline tu- 

 bercles ; ostioles papillate, at length pertuse. Spores ellip- 

 soid or oblong, somewhat large, three-septate, reddish-brown; 

 each loculament contains a peculiar rhomboid cellule, which 

 gives the spores a very peculiar appearance. (E. B. 2607.) 



On the smooth bark of various forest-trees, as the beech 

 and ash, in lowland districts. Its spermogones are mar- 

 ginal, situated along or parallel to the black sinuous lines 

 which denote the boundaries of each individual thallus ; they 

 are depressed, blackish, and about the size of the ostioles of 

 the apothecia. The sterigmata are linear, short, and nearly 

 as slender as the spermatia, which are linear, curved, and 

 very numerous. 



ft Perithecium dimidiate. 



2. Verrucaria epidermidis [epidermis, the cuticle or 



