194 
Mycologia 
33. Uromyces columbianus Mayor, Mem. Soc. Neuch. Sci. 
Nat. 5; 467. 1913. 
On Carduaceae: 
Melanthera canescens (Kuntze) O. E. Schultz, Gales, 
June 12, 1912, 28) Ahasco, Jan. 28, 234, 274, Oct. 12, 
3564, Sjd8; Corozal, Feb. 12, 421; Yauco, Oct. 3, 3138; 
Mayagiiez, April 12, 1022; Vega Baja, May 18, 2041, 
2045, May 21, 1895, ipio, 1922; Cayey, June 5, 2175; 
Cabo Rojo, June 15, 2255; Rosario, Oct. 27, 3837; 
Utuado, Nov. 8, 4423, 4684; Quebradillas, Nov. 22, 
5190; San German, Dec. 12, 5831, 5834; Guayanilla, 
Nov. 13, 3917, 5918 ; River junction below Utuado, Dec. 
16, 6039, Dec. 17, 6070, Dec. 30, 6860, 6864) Jayuya, 
Dec. 17, 6044, 6045. 
The rust was obtained on the phanerogamic collection of the 
same host species made by Mr. & Mrs. A. A. Heller 138, near 
Rio Piedras, P. R., May 13, 1899. 
Since the work on Steven’s Porto Rican rusts began, the ex- 
cellent and detailed study of the rusts of the United States of 
Colombia by Dr. Eug. Mayor of Neuchatel, Switzerland, has been j 
issued. In this work is a full description of the aecia, uredinia ' 
and telia, with a fairly good cut illustrating the urediniospores 
and teliospores of this species. The type is on Melanthera 
aspera (Jacq.) Steud., Andes centrales, dep. Antioquia, IMedellin I 
and Envigado, alt. 1550 m., II and III, August 19, no. 236, sup- 
plemented by a number of other collections. , 
Pycnia occur in the Stevens collection on nos. 28, 1910, 1922, 
2043, 2173 and 3917 accompanying the aecia, and probably on a 
number of others. In each case the collection also shows uredinia 
and telia. The pycnia are subepidermal, globoid or flask-shaped, ! 
inconspicuous, about 100 fi in diameter. 
The rust bears the usual characters that entitle it to a place in 
the genus Nigredo, in which it becomes Nigredo Columbiana 
(Mayor) comb. nov. 
The host belongs to a group of forms that is difficult of sepa- 
ration into species. The Stevens collections are fortunately well 
supplied with inflorescence at various stages of maturity. Some 
