Leaf Curi. and Plum Pockets. 339 



The mycelium is very abundant in the tissues of the hypertro- 

 phied fruits, forming a well developed network of threads between 

 the cells as in other species of this type. 



These are the only specimens on P. americana Marshall of this 

 species which I had the opportunity to examine. Other speci- 

 mens of hypertrophied fruits of P. americana were collected 

 near Ithaca, N. Y., during June, 1894, and judging from a pho- 

 tograph which I have seen of them the form of the hypertrophied 

 fruit is quite different. The specimens have either been mislaid 

 or lost so that at this time there is no means of examining them 

 to see whether they belong to this species or to E. communis 

 Sadebeck. 



Exoasciis commu7tis Sadebeck. 



Sadebeck* reports this species on Prunus americana Marshall 

 from the United States, collected by Bartholomew. To it I have 

 also referred specimens collected by Seymeur at Madison, Wis., 

 June 3, 1886, and distributed as Taphri7ia pruni^ (Berk.) Tul. 



Specimens on the fruits of cultivated varieties of P. americana 

 communicated by Prof. Pammel, and collected in Iowa, show a 

 much distorted fruit in many specimens, especially of the 

 " Cheny " variety. In some of these fruits only one side appears 

 to be affected, resembling in this respect very much, the fruits of 

 P. angustifolia deformed by E. mirabilis var. tortilis Atkinson. 

 The form of the stalk cells also seems to be nearer those of that 

 species than of E. communis, and I do not feel like definitely locat- 

 ing the form until we know more about the relation of these 

 hypertrophied fruits of the cultivated varieties of P. americana to 

 the deformed buds which also occur on P. americana, and which 

 appear to be identical with those on P. angustifolia and P. hor- 

 tulana. 



The asci of the "Cheny" and "Baldwin" varieties of the 

 form on the fruit of P. americana are shown in detail in figures 

 40-43, 42 representing the asci of the Baldwin variety. 



*Die parasitischen Exoasceen. Ab. a. d. Jahrb. d. Hamb. Wiss. Anst. X. 2, 

 p. 47, 1893. 



t Seymour and Earle, Economic Fungi, No. 13. 



