214 



New York Uncinulce. 



are readily distinguished from each, other by the number 

 of spores in each sporangium ; those of the second group, 

 by their appendages. 



Tabular Arrangement of the Speeies. 

 § 1. Appendages numerous, (thirty or more) a. 



a. Sporangia with eight spores, . . circinata. 

 a. Sporangia with six spores, . . TorreyL 

 a. Sporangia with four spores, . . adunca. 



a. Sporangia with two spores, . . macrospora. 



§ 2. Appendages few, (less than thirty) 6. 



b. Appendages white, flexuous 



toward the tips, flexuosa. 



b. Appendages white, not flexuous, Clintonii. 



b. Appendages colored, .... Ampelopsidis. 



1. Uncinula circinata C. & P. (Jour. Bot p. 12, 1872). 

 Mycelium effused, evanescent or subpersistent ; concep- 



tacles large .007 inch in diameter, subglobose ; appendages 

 numerous, simple, slender, as long as the diameter of the 

 conceptacle, circinate at the apex; sporangia 8- 16, oblong 

 or narrowly ovate; spores 8, broadly elliptical, .0007 

 inch long. Figs. 7-9. 



Lower surface of maple leaves. Watkins and ' Green- 

 bush. September and October. 



This plant sometimes occupies the whole of the lower 

 surface of the leaf. It seems to delay the usual autumnal 

 change in the color of the leaves attacked by it, for some 

 of those partly occupied by the fungus were found to be 

 green in the affected spots when the unoccupied adjacent 

 parts had assumed their usual autumnal hues. 



2. Uncinula adunca Lev. (Handbook of Brit. Fung., p. 646). 

 Mycelium variable, usually dense and persistent, effused 



or growing in spots; conceptacles .005 inch in diameter; 

 appendages numerous, about as long as the diameter of 

 the conceptacle; sporangia 8 - 12, subelliptical ; spores 4 — 

 elliptical, .0007 — .0008 inch long. Figs. 1-3. 



