SYSTEMATIC TREATMENT OF FAMILIES, GENERA, 



AND SPECIES 



1. VERRUCARIACEAE 



Thallus crustose, partly within the substratum, or rarely imbedded in the 

 lichen host, devoid of differentiation into layers; perithecia more or less immersed, 

 single, upright, the ostiole terminal; paraphyses very soon gelatinizing and becom- 

 ing indistinct or rarely persistent and distinct. 



The algal hosts are Protococcus and Pleurococcus. 



A. Paraphyses persistent, but indistinct 



B. Spores non-septate 7. Thrombium 



B. Spores transversely and longitudinally septate 8. Microglaena 



A. Paraphyses becoming slimy, disappearing or wanting 

 B. Spores non-septate 



C. Spores 1-8 in each ascus 1. Verrucaria 



C. Spores many in each ascus 2. Trimmatothele 



B. Spores septate 



C. Spores transversely 1-3 -septate 



D. Thallus imbedded in that of the host; spores 1-septate . 4. Thelidiella 

 D. Thallus superficial, crustose; spores 1-3-septate .... 3. Thelidium 

 C. Spores transversely and longitudinally septate 



D. Apothecia more or less immersed; ostiole rarely visible . 5. Polyblastia 

 D. Apothecia immersed in raised areas; ostiole protruding . 6. Staurothele 



1. Verrucaria Scop., Intr. Hist. Nat. 61. 1777. 



Thallus crustose, partly or wholly within the substratum, the superficial 

 portion warty or areolate, thin to thick, seated upon a well-developed hypothallus, 

 the imbedded portion usually indicated at the surface by a discoloration of the 

 substratum, devoid of differentiation into layers; perithecia minute to small, more 

 or less immersed, 1-several in each thalloid wart or areole, or later protruding, the 

 wall dimidiate or complete, the superficial portion flat to more commonly hemi- 

 spherical or convex, the ostiole minute, commonly inconspicuous; hypothecium 

 hyaline to brown; hymenium hyaline or brownish above; paraphyses soon gelat- 

 inized and indistinct; asci clavate; spores 8, hyaline to rarely brownish, non- 

 septate. 



The algal host is Pleurococcus. 



A. Thallus on rocks along seacoast or inland streams 

 B. Spores rarely more than 10 fi in length 

 C. Thallus more or less uniform 



D. Thallus smooth to slightly rough, areolate .... 2. V. ceuthocarpa 

 D. Thallus marked by many minute spots or lines . . . . 1. V. striatula 



C. Thallus interspersed with very thin areas 3. V. subsuperficialis 



B. Spores rarely less than 10 n in length 



C. Perithecia rarely more than 0.15 mm. across 



D. Spores 7-15 X 4-8 fi 5. V. mucosa 



D. Spores 16-22 X 6-10 /x 8. V. papillosa 



C. Perithecia rarely less than 0.15 mm. across 

 D. Spores rarely more than 20 m in length 



E. Perithecia rarely more than 0.3 mm. across 



F. Spores 14-20 X 5-8 fi 6. V. aethiobola 



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