G8 



Peridermium Cerebrum, Peck. 



Peridia large, convex, erumpent, irregularly confluent, forming brain-like 

 convolutions, white, rupturing irregularly, tlie cells radiate-striate on the 

 margin; spores ovate-elliptical or subglobose, rough, yellow, .0008'-.0011' 

 long. 



Trunks and branches of young pine trees, Pimis rigida, forming 

 excrescences half an inch to two inches in diameter. Center, /. 

 A. Lintner. 



Roestelia aurantiacaj Peek, 



Peridia cylindrical, fragile, soon lacerated, fugacious, white ; spores sub- 

 globose, bright orange, about .001' in diameter, with a thick hyaline epispore. 



Unripe fruit of Amelanclder Canadensis. New Baltimore, /. 

 L. Zabriskie. Keene. July. Also on the unripe fruit of Crataegus. 

 Buffalo, Clinton. 



The color of the spores will enable this species to be easily recog- 

 nized. 



Aecidium Gerardiae, Peck. 



Spots small, suborbicular, scattered, yellowish-green, peridia usually few, 

 small, short, the mouth fringed with spreading or recurved teeth ; spores 

 orange, .0008' in diameter. 



Leaves of Gerardia quercifoUa. Highlands near Cold Spring. 



June. 



Aecidium album, Clinton. 



Spots none ; peridia scattered, short, white, the margin subentire ; spores 

 subglobose, white, about .0008' in diameter. 

 Under surface of leaves of Vicia Americana. Buffalo, Clinton. 



Aecidium Lycopi, Gerard. 



Spots yellow ; subiculum more or less thickened ; peridia short, scattered 

 or crowded, margin crenate ; spores pale yellow. 



Leaves, stems and petioles of Lycopus Europaeiis. Pough- 

 keepsie, Gerard. Buffalo, Cli)iton. June. 



Aecidium Hydrophylli, Peck, 



Spots small, few, yellow, with a pale greenish border ; subiculum thickened 

 whitish ; peridia few, generally crowded, short, the margin subcrenate ; 

 spores bright yellow or orange; spermogonia central, on the opposite side. 



Under surface of Icavos of IlgiJmpJ/i/Jhnii f'fn/fidr)/se. C'iilskill 

 Monn tains. Juno. 



