May 1907] An Apple Rot Due to Volutella 97 



or the stem end, than at other points. The rot occurs at either 

 end of the fruit more often than elsewhere, because it is at these 

 places that the cuticle is most liable to injury. 



The tubercular development places the fungus unquestion- 

 ably among the Tuberculariales. Further the road is not so clear. 

 Judging strictly from the color of the mycelium it must go to 

 the Dematiae, but a glance over its possible kin there reveals none 

 which are of certain affinity. Admitting that it is possibly a 

 Mucedineae, it clearly must belong to the genus Volutella. This 

 genus is made up mainly of light colored fungi, though several 

 of the genus are very dark, notably V. Acalyphae, oxyspora, 

 Violae, CitruUi and Allii. From a structural viewpoint this 

 fungus seems much closer to Volutella than to any of the Dema- 

 tiae. In view of the purely physiological nature of the color 

 character, as shown by our cultures, it being dependent upon the 

 presence of carbohydrates — which is present in abundance in 

 the natural medium of the apple — we believe we are doing no 

 violence to facts in placing it in the genus Volutella. 



As a Volutella it stands closest to the species named above, 

 yet is distinct enough from them to be regarded as a separate 

 species for which a description is herewith proposed. 



It dififers from oxyspora in larger sporodochium, 150-400 

 y. and longer setae, shorter spores and longer basidia ; from 

 Citrulli in shape of spores ; from Allii, sporodochia larger not 

 convex or elongate, setae longer ; from Violae in character of 

 sporodochium, see Bot. Gaz. 26:85, P^- XIV: from Acalyphae 

 in size of spores. 



Volutella fructi Stevens & Hall n. sp. 



Sporodochia numerous in concentric circles, early subcuti- 

 cular then erumpent, elevated, black, 1 50-400 /x diameter; my- 

 celium, black in presence of carbohydrates, otherwise hyaline. 

 Setae; distributed throughout sporodochium, black 0-5 septate, 

 acute, smooth. 100-400/* long, 5 to 8 /a thick. Sporophores ; 

 elongate, hyaline, simple, 25-35 by 3 /a. Conidia ; hyaline or 

 very slightly olivaceous, continuous, smooth, oblong-fusoid to 

 falcate-fusoid 17 to 23 by 2.5 to 3.5^1. 



Habitat: fruit of Pyrus Mains. North Carolina, type N. C. 

 Agr. Experiment Station No. 780. 



EXPLANATION OF FIGURES. 



Fig. I. Three apple cells invaded by the mycelium of Volutella. 



Fig. 2. Showing early stages in the development of the sporo- 

 dochium before the rupture of the cuticle, (a) Cuticle 

 of the apple ; (b) Columnar arrangement of the fun- 

 gous hyphae. 



