BULLETIN 



OF THE 



TORREY BOTANICAL CLUB 



Vol. Vlll.l New York, May, 1881. [No. 5. 



45. Two New Species of Fungi. 



By Chas. H. Peck. 



An interesting, and, so far as I have been able to ascertain, an un- 

 described fungus was recently sent me from Illinois. It inhabits oak 

 leaves and occurs in two forms, one conidial, the other ascigerous. 

 The conidial form grows in minute white tufts, having a somewhat 

 radiate or stellate appearance, especially when viewed through a mag- 

 nifying glass. These tufts occur on the lower surface of the leaf and 

 are generally sufficiently numerous to cause the leaf to appear as if 

 it had been sprinkled on that surface with flour. The upper surface 

 is obscurely mottled with minute pale or yellowish spots, which are 

 placed opposite the tufts beneath. The hyphae or flocci are com- 

 pound and are composed of several somewhat obconic masses of 

 obovate or short-clavate cells, the masses being placed one above 

 another in a proliferous manner, and together forming a sort of short, 

 thick, submoniliform filament or pagoda-like structure. The conidia 

 are also in masses or tufts, which are nearly elliptical in outline, and 

 arranged in verticels around the flocci, they being attached to the 

 upper or thicker exterior part of the component cells. In each tuft 

 there are usually seven, though sometimes but six, oblong or subcyl- 

 indrical, slightly curved, colorless conidia, compactly arranged in a 

 circle and forming a .kind of cylinder or palisade around a single' 

 central one. Thus each tuft contains in all seven or eight conidia.. 

 This form of the fungus develops a little before the ascigerous form. 

 In the specimens before me, some of the leaves have only the conid- 

 ial form on them, others have both forms intermingled. In the lat- 

 ter, the ascigerous form appears frequently to have developed on the 

 very spot previously occupied by the conidial form. The ascigerous 

 form consists of numerous black dots or cushions scarcely broader 

 than the conidial tufts. Both surfaces of the leaf are more or less 

 tinged with brown in the places where these fungus dots are the 

 most numerous. A thin, flat, pale, soft or waxy stratum or receptacle 

 first makes its appearance. This produces numerous globose asci, 

 which are at first pale and contain eight oblong triseptate spores, one 

 or more of the cells of which are divided by short longitudinal septa, 

 so that the spores might be called muriform. They are at first pale 

 or colorless, but soon become very dark-colored, and give the 

 black hue to the fungus dots. The asci develop in the stroma-like 

 receptacle, but, when mature, they appear to lie upon or near the 

 surface, and almost cover the receptacle and conceal it from view. 

 ^-^ a few instances they become slightly longer than broad and take " 

 a somewhat ovate shape, but usually they are globose even when ma- 

 ture. 



I know of no genus to which this fungus can properly be referred, 



and am therefore obliged to institute one for it. 



