66 BOTANICAL GAZETTE [JULY 
This prompt and very abundant appearance of the uredo could be 
interpreted only as the result of the aecidial infection, for corn rust had 
not yet appeared out of doors, and even if it had, such an unusual attack 
following closely within the time limit of incubation would be highly improb- 
able. It may therefore be considered proved that the aecidium of Puccinia 
Sorghi Schw. occurs upon Oxalis, and a verification with teleutosporic 
material can be confidently undertaken in due time. 
There are but seven or eight records in literature of the collection of 
aecidia on Oxalis, and there is little doubt, if any, that in every case the 
aecidium belonged to Puccinia Sorghi. They are as follows: 
1876. Collected on Oxalis Bowiei Lindl. near Somerset East, Cape 
Colony, South Africa, by P. MacOwan, and issued in Thuemen’s Myco- 
theca universalis, no. 1226. It was given the name of Aecidium Oxalidis by 
Thuemen and described as a new species in Flora 63:425. 1876. I have 
seen several specimens from this collection, and can detect no morphological 
difference between the African fungus and the one from which I raised 
uredospores. The probability of its being the same species is somewhat 
increased by the fact that Puccinia Sorghi Schw. on cultivated corn was 
also found near Somerset East by the same collector (Flora 63: 569. 1876) 
in the preceding autumn. 
1877. Collected on Oxalis violacea L. at Ames, Iowa, by the writer 
(Bull. Iowa Agric. College —:167. Nov. 1884). Only a few affected leaves 
were found. 
1887. Collected on Ovalis stricta L. at Manhattan, Kan., by W. A. 
Kellerman (Eliss & Everhart’s North Amer. Fungi, no. 2210) and M. A. 
Carleton (Bartholomew’s Kansas Uredineae in Trans. Kans. Acad. Sci. 
16:190). These citations probably represent only one collection. The 
specimen in N. A. F. agrees with the Indiana collection, except that the 
host is a different though closely related species. 
1889. Collected on Oxalis violacea L. at Lincoln, Neb., by H. J. 
Webber (Bull. Neb. Agric. Exper. Sta. no. 11: 333, and Rep. Neb. Bd. 
Agric. 1889:211), who speaks of it as rare; and also on the same host at 
Weeping Water, Neb., about 50*" from Lincoln, by T. A. Williams (Rep- 
Neb., Bd. Agric. /. ¢.), who reports it as common. Ihave not seen these 
collections. 
1893. Collected on Oxalis corniculata L. at Bozen in the Austrian 
Tyrol, by J. Peyritsch. This was published by Dr. P. Magnus in the 
men from this collection, or the published article, but I do not doubt that 
