84 Witson: NortTH AMERICAN PERONOSPORALES 
Cystopus Euphorbiae Cooke & Massee, Grevillea 20: 106. 
1892. 
The roughened conidia bespeak a closer relationship with the 
Uredinales than with the present genus. 
Cystopus Salsolae and C. Schlechteri P. Sydow, Hedwigia 
Beibl. 38: 142. 1889. 
Authentic material of both these species has been examined. 
In both instances the host is covered with white spots which 
closely simulate the sori of A/bugo and answer to the description in 
the diagnoses of these species. A microscopic examination of 
these spots failed to show anything except crystals of some chem- 
ical. These answer fairly well to the measurements given, but 
show no membrane or other parts as described, for the spores. 
Nothing more similar to conidia, however, was observed. The 
spores described as oOspores are present in fair abundance in 
the material of both species. They are borne apparently singly, 
at the apex of isolated conidiophores, and are the conidia of some 
species of Hyphomycetes and rather closely related to Coniospor- 
zum or Torula. 
New York BoTANICAL GARDEN, 
