74 Witson: NorTH AMERICAN PERONOSPORALES 
tive size of the areolae of the odspores, there do not appear to be 
sufficient grounds for the separation of the material examined into 
additional species. Especially is this true in regard to de Bary’s 
Cystopus spinulosus, which is supposed to have pronounced spines 
on the odspore. Dr. A. Fischer has examined the type specimen 
of this species and declares the character unreliable.* This is borne 
out by the more recent investigations of Dr. Magnus.} Since then 
_ Berlese has figured the spinulose odspores,{ using the material 
distributed by von Thiimen (Myc. Univ. 7423) on Lnula salicina 
from Parma. The figures of the entire oospores have a spinulose 
appearance due to the projection of the reticulations beyond the 
margin of the spore. The figure of an enlarged portion of the 
epispore looks very unlike anything found by me in the packet of 
this material, or, for that matter, in any other, as no such epispore 
has been observed by me in any specimen of the genus. 
South American material from hosts of the tribes Astereae and 
Eupatorieae was examined. Oospores similar to those produced 
on species of other tribes of this family were found on Ageratum 
conyzoides from Ecuador. From the same host Ule, in 1884, col- 
lected material in Brazil which has been referred to A/bugo brasilt- 
ensis (Speg.) P. Hennings § and which was issued in Rabenhorst- 
Winter-Pazschke Fungi Europaei 3873 as Cystopus Ti ragopogons. 
From a comparison of these two South American specimens it 
appears. that Spegazzini’s species is merely a synonym of A. Tra- 
gopogonis. Two other South American species, Cystopus Mikaniae 
Speg. and Albugo Solivae Schrot., have been described, but no 
material of either is at hand for examination. Inasmuch as the 
original descriptions of these species are scarcely distinctive and the 
hosts are closely related to species known to be hosts of A. Trago- 
pogonis, it is very probable that they are also synonyms of ‘that 
species. In addition to the above, another species, Cystopus pul- 
verulentus B. & C., was described from an unidentified species of 
Compositae from Cuba. According to Dr. Farlow || the type ‘* cal 
not be traced in Herb. Curtis by the number cited in the original 
* Rabenh. Krypt. Fl. ed. 2. 14: 422. 1892. 
+ Ber. Deutsch. Bot. Ges. 11: 327-330. p/. 15. 1893. 
tIcon. Fung. Phyc. f/. 5. 1898 
3 Hedwigia 35: 212. 1896. 
|| Bibl. Index N. Am. Fungit: 177. Igo. 
