Witson: NortH AMERICAN PERONOSPORALES 415 
Cucumis sativus L., Florida, Hume 24 ; Massachusetts, 
Humphrey; New Jersey, Halsted (N. Am. Fungi 
2426a; Econ. Fungi gz), Stevens ; Maryland, Dorsett ; 
Ohio, Se/by (Phyc. Prot. 77g); West Virginia, Sheldon. 
? Cucurbita maxima Duch., New Jersey, Halsted (N. Am. 
Fungi 24260). 
Cucurbita ovifera L., Ohio, Duvet 
Cucurbita Pepo L.., Ghio; Duvel. 
Lagenaria vulgaris Ser., Ohio, Duvel. 
Micrampelts lobata (Michx.) Greene, Ohio, Se/éy. 
Momordica balsamina ., lowa, Arthur. 
Mukia scabrella Arn., Ohio, Duvel. 
The following additional hosts are reported from within our 
limits: Cucumis Anguria L., Melothria scabra Naud., Momordica 
charantia L., Sicyos angulatus L.., Trichosanthes colubrina Jacq. 
TYPE LOCALITY: Cuba, on some unidentified species of Cucur- 
bitaceae. ; 
DisTRIBUTION : New Hampshire to Minnesota, Texas, Florida, 
and Cuba. Also in South America, Europe, Asia, and Africa. 
IconEs: Riv. Pat. Veg. 9:125. f. 27, Rep. Mass. State Agr. 
Exp. Sta. 8: p/. 2. f. rz—-rg; Bull. Ohio Agr. Exp. Sta. 89 : pi. 
7; Rep. Fla. Agr. Exp. Sta. 1899-00: //. z; Rev. Myc. 22: pi. 
203. f. 7-9; Rep. Conn. Agr. Exp. Sta. 1904: p/. 37. 
2. Pseudoperonospora Celtidis (Waite) 
Peronospora Celtidis Waite, Jour. Myc. '7:105. 1892. 
Plasmopara Celtidis Berlese, Icon. Fung. Phyc. 16. 1898. 
Peronoplasmopara Celtidis Clinton, Rep. Conn. Agr. Exp. Sta. 
1904: 334. 1905. 
Hypophyllous, infected areas brownish, limited by the veins, 
from less than I mm. up to covering a large portion of the leaf; 
epiphyllous discoloration purple with a more or less pronounced 
yellowish margin ; conidiophores scattered, 200-320 x 6-8 pw, 4-5 
times branched, the ultimate branchlets straight or slightly re- 
curved, about 5-8 » long; conidia elliptic, 12-26 x 20-4o-p, 
smoky or somewhat purplish ; odspores in the leaves, 26-45 »; 
epispore thin, yellowish-brown, irregularly thickened ; oogone 
persistent, thin-walled, smooth 
This species is remarkable as the only member of the order 
