Arthonia aleuromela Nyl., sp. nov. Thallus albus sub- 

 farinaceus chrysogonidicus tenuissimus; apothecia subrotundata vel 

 oblonga, prominula, latit. 0.4-0. 5mm; spora oblongo-oviformis parte 

 inferiore attenuata, 1-septata, long. 0.010-11, crass. 0.003mm. In 

 toto gelatina hymenialis coerulescens, dein obscurata. 



Thallus detritus subaureus, CaCl vix reagens. Gonidia chroole- 

 poidea fulvescentia. 



On bark of Quercus sp. West Virginia, near Nuttallburg, alt. 

 2000 feet, L.-W. Nuttall coll. no. 1182. 



(INSERT OPPOSITE PAGE 182). 



