OP ARTS AND SCIENCES. 85 



pale yellow spots on the leaves, which soon thicken and swell, becom- 

 ing convex above and concave below, the color changing from yellow 

 to a dark purple. The asci are clavate, 30-38 fj. long by about 6-8/x, 

 broad, and contain eight round or ovate spores 3-4/x in diameter. 

 There is still another related species, if not a variety of Ux. deformans 

 itself, which grows on Hhus copalUna in Eastern Massachusetts. The 

 leaves attacked become very much wrinkled and curled, and have a 

 lurid purple color. The asci are somewhat stouter than in the form 

 on Potentilla, being 24-30/^ long by 11-15/a broad, and the spores are 

 spherical and measure 3.5-4,5/i,. If I am not mistaken, a similar form 

 on an African Rhus has been reported by Magnus, but I am unable 

 to refer to his description. 



