236 ARTHUR-BISBY— TRANSLATION OF SCHWEINITZ'S 



y Subgen. rcestelia or ceratites. 



2899. 89. C. R. Cylindrites, Lk. n. 172, Syn. Car. 432, under this name are 



included the following Gseomata, perhaps to be separated as 



species. 

 a. C. Cratsegi punctatae, pseudoperidia divergent fibrous, swollen in 



the middle — white. Pennsylvania. 

 /3. C. Cratsegi arborescentis, spots small, red, pseudoperidia not fibrous, 



of various forms, fuscous-red. Near Fayetteville, Carolina. 

 7. C. Oxyacanthse, very large, very frequent near Philadelphia in 



hedges. 

 5. C. Mali, on leaves of Pyrus malus and coronaria, spots small but 



effuse. Pseudoperidia minute. 

 (432. 3. [^cidium] Cratsegi var. Oxycanthse. A rare species on 



leaves of various Cratsegi.) 



Represented in each of the four forms by specimens and orig- 

 inal packets from which it is possible to show that Schweinitz's sur- 

 mise was right, that they belonged to four distinct species. 



a- Represented by one leaf, 8 cm. long, of what is probably 

 Cratcegus punctata Jacq., mounted, bearing six groups of aecia, and 

 by two smaller but similar leaves, about 6 cm. long and 4.5 cm. broad, 

 with no mature secia, in the original packet, labelled inside " Rcestelia 

 (cornuta) oxyacanthse In Crat. pyrifol Bethl," with "cornuta" 

 crossed out, and " Caeoma cylindrites " written above, and outside 

 labelled "Caeoma (Ceratites) Cratcegi piinctatce Bethl aff. penicillat." 



The rust proves by microscopic examination to be the aecia of 

 Gymnosporangium globosum Farl. 



/?. Represented by a mounted leaf, 4.5 cm. long and about same 

 width, of what is probably Cratcegus viridis L. (C. arhorescens Ell.), 

 bearing four groups of aecia, and by half of a similar leaf with one 

 group of pycnia, in the original packet, labelled outside " Caeoma 

 (Ceratites) ^cidium Cratcegi arhorescentes Fayetteville." Half of 

 a similar but smaller leaf, with one group of secia, is in the Michener 

 collection at Washington, property of the U. S. Department of Agri- 

 culture. 



This aecial rust is that of the very distinctive southern species 

 Gymnosporangium hyalinum (Cooke) Kern, whose telia are not yet 

 known. 



y. Represented by a large, 4.5 cm. broad and originally much 



