28 THE BITTKR ROT OF APPLES. 



have concerning the influence of different substrata on morphological 

 characters of plants. This is particularly true of saprophytic fungi, 

 which, like the ripe-rot or bitter-rot fungus, can grow on media of 

 widely different chemical compositions. An abundant food supply 

 may result in the production of very large spores, just as a meager 

 supply may be followed by the formation of smaller spores. 



The various fruits under consideration have a different structure and 

 they differ chemically. It might, therefore, be expected that there 

 would be slight differences in the structure of the fungus, and also in 

 the external appearance of diseased fruits. 



In cultures the various forms behave similarly. No such distinct 

 physiological strains as were described for Neocosmospora vasinfecta 

 by Erwin F. Smith (1899, p. 39) could be established. This is prob- 

 ably due to the more or less saprophytic nature of the fungus. 

 Olcnosporium fructigenum Berk, is not bound so strictly to the apple 

 cell as the root-rot fungus is bound to the cowpea, the cotton, or the 

 watermelon. 



Assuming, then, that the four species mentioned above are one and 

 the same, it becomes necessary to choose one of the four specific names. 

 According to the generally accepted rules of nomenclature, the name 

 under which the fungus was first known takes precedence, and in this 

 case it is Glceosporium rufo-macuians (Berk.) v. Thi'imen. 



This would have been the name of the bitter- rot fungus but for the 

 discovery of the perfect or ascus stage. In 1002 Clinton placed the 

 bitter-rot fungus in the genus Gnomoniopsis Stoneman. 



In 1895 Miss Stoneman described a new genus Gnomoniopsis in 

 which she placed (after obtaining in cultures the ascosporic stage) the 

 following fungi, hitherto known only in the imperfect stages as mem- 

 bers of the Melanconiacea?: Glosospo?'ium cingulata Atk., Glceosporium 

 piperatum E. &E., Colletotrichum cinctum Berk. & Curt., and Ool- 

 letotrichum rubicolum E. & E. Clinton included the bitter-rot fungus 

 Gloeosporium fructigenum Berk, in this group and named it accord- 

 ingly Gnomoniopsis fructigenum (Berk.) Clinton. It is under this 

 name that the fungus now stands. 



In establishing the genus Gnomoniopsis Miss Stoneman, however, 

 overlooked the fact that six years prior to her publication Berlese 

 (1892) used the name Gnomoniopsis for a group of fungi very different 

 from the perfect form of the Gloeosporium which she described. 

 Clinton, in accepting Miss Stoneman's name, likewise overlooked the 

 name published by Berlese. The latter raised the subgenus Gnomoni- 

 opsis of the genus Gnomonia as used by Winter (1887) to generic rank, 

 making the species Gnomonia chamaemori (Fries) the type, and includ- 

 ing in the new genus the former Gnomonia misella as a variety of 

 Gnomoniopsis chamaemori (Fries). Lindau (1902) accepts Miss Stone- 

 man's genus Gnomoniopsis. The generic use of Gnomoniopsis by Ber- 

 lese in 1892 clearly invalidates Miss Stoneman's name, and it becomes 



