114 
Palmer, No. 680, 1887, Los Angeles Bay, Guaymas, Mexico. Ex. Herb. 
Bot. Div. Dept. Agric. J. H. Simpson, July 11, 1890, Sarasota Bay, 
Manatee County, Fla. Ex. Herb. Bot. Div. Dept. Agric. W. T. Swingle, 
No. 4008, July 4,1891, Eldorado, Lake County, Fla. W. T. Swingle, No. 
4009, July 13, 1891, common on sandy land along railroad, Eldorado, 
Lake County, Fla. 
On Boerliaavia hirsuta , Willd. Schott, No. 21, Feb. 12, 1865, Merida, 
Yucatan, Mexico. Ex. Herb. Bot. Div. Dept. Agric. W. T. Swingle, No. 
4010, July 13, 1891, Eldorado, Lake County, Fla. The host may not be 
this species, as it was too young for positive determination. 
On Boerliaavia Sonorw, Bose. Edw. Palmer, September 16-30, 1890, 
Alamos de Calorce, Mexico. Ex. Herb. Bot. Div. Dept. Agric. 
On Boerliaavia spicata , Choisy. Geo. Yasey, 1881, Las Cruces, N. Mex. 
Ex. Herb. Bot. Div. Dept. Agric. 
On Boerliaavia viscosa , Lag. et Bodr. Beverchon, No. 791, June, 1880, 
Dallas, Dallas County, Tex. Ed. Palmer, No. 212, Aug. to Nov., 1885, 
S. W. Chihauhua, Mex. 
On Boerliaavia Xanthii, Watson. Edw. Palmer, No. 681,1887, Guay- 
mas, Sonora, Mexico. Ex. Herb. Bot. Div. Dept. Agric. 
I found this interesting Albugo in Florida during the summer of 1891, 
and upon my return to Washington examined the specimens of Nycta- 
ginaceae in the herbarium of the botanical division of the Department of 
Agriculture, through the kindness of Dr. George Yasey and Mr. J. N. 
Bose. I was agreeably surprised to find many specimens here, as may 
be seen from the foregoing list. I am much in doubt as to the identifi¬ 
cation of the material, and would not publish this notice if it were not 
largely with the hope that it may call forth further observations and 
perhaps result in the finding of oospores. 
The first mention I have found of Albugo occurring on nyctagina- 
ceous plants is by Zalewski,* in 1883, who reports an A lbugo on Boerliaa- 
via from Ceylon and from La Plata which he refers to his Cystopus 
amarantacearum (=Albugo amaranthi (Schw.) O. Kze.), on the strength 
of the conidial characters, since he was unable to find oospores. In 
speaking of this form he says: “die Conidien sind aber hier von denen 
von C. Amarantacearum gar nicht zu unterscheiden.” I find, however, 
that the specimens reported above (also lacking oospores) seem to differ 
constantly from Albugo amaranthi in several points. First, the conidia 
are in every case yellowish as seen in mass, being almost exactly of the 
color of those of A. portulaece and unlike those of A. amaranthi , which 
are white. Second, the terminal conidium shows in every case a very 
much thicker internal equatorial band which is dusky or even brown in 
color, while a similar structure in A. amaranthi is colorless or nearly 
so. Yery possibly further differences will be found to exist, since I have 
not had time to make an exhaustive examination of the two species. 
These constant differences, together with the failure to find oospores in 
* Zur Remit, tier Gatt. Cystopus L<$v. Vorliiufige Mitt, in Bot. Centralb., loc. cit., 
pp. 222-223. 
