

204 BOTANICAL GAZETTE Imarch 



On Cassiaceae: Bauhinia divaricata L., Cuba, Guanajuoto; B. Pauletia 

 Pers., Porto Rico; B. porrecta Sw., Jamaica. 



Type locality: Constant Spring, Jamaica, on Bauhinia sp. 



Distribution: Mexico and the West Indies. 



Illustration: Ark. Bot. Stockh. 4: pi. 2. jig. 14. 



Literature: Sydow, Monog. Ured. 2:84. 1909; Saccardo, Syll. Fung. 



2io52-553- 1912. 



* 



This species may perhaps be distinguished from the preceding 

 by the somewhat reduced length and breadth of the teliospores, 

 the wall thickness often being less also. The differences described 

 by Vestergren (loc. cit.) have not been found to hold entirely 

 throughout the collections at the Arthur herbarium. Some differ- 

 ences, however, are still to be found between the two species of rust, 

 and they are maintained as separate species, at least pending 

 further collections. 



Vestergren's supposition that Uromyces jamaicensis is a 

 micro- Uromyces has been corroborated by the discovery of pycnia 

 associated with telia upon a Cuban specimen of Bauhinia divaricata. 

 The specimen upon B. porrecta collected by Thaxter has not been 

 seen, but Vestergren's type collection has been examined. 



Vestergren separated 17 species of Uromyces upon the host 

 Bauhinia, for none of which aecia are known. Evident similarities 

 are shown between the species as he described and figured them. 

 Uromyces only are known to occur upon Baiihinia. Many species 

 of Bauhinia occur in the tropics; related genera, as shown by 

 Engler and Prantl's classification, are chiefly genera upon which 

 rusts have not yet been found. The reticulate nature of the 

 sculpturing upon the surface of the teliospores of these two species 

 is minute, but evident under higher microscopic power. Figs. 7-10 

 illustrate the two species. 



4. Uromyces abbreviatus Arth. Bull. Torr. Bot. Club 4 2: 5 8 7- 



19*5. 



O. Pycnia hypophyllous, scattered among the telia, inconspicu- 

 ous, subepidermal, deep seated, dark honey-yellow, globose or 

 flattened globose, 115-200 jx in diameter by 95-140 /x in height; 

 ostiolar filaments dense, often falling away, up to 60 /x in length. 



III. Telia hypophyllous, rarely also epiphyllous, densely 

 clustered, becoming scattered over considerable areas, roundish, 



