196 
Mycologia 
Peronospora destructor (Berk.) Casp. ; Berk. Outl. Brit. 
Fung. 349. i860 
Botrytis destructor Berk. Ann. Mag. Nat. Hist. II. 6: 436. 1841. 
Peronospora Schleideni Unger, Bot. Zeit. 5: 315. 1847. 
Peronospora Schleideniana Unger : De Bary, Ann. Sci. Nat. IV. 
20: 122. 1863. 
The synonymy of this species -has been discussed briefly by Pro- 
fessor Whetzel, 3 but as this author retains the last name in prefer- 
ence to the first it may not be out of place to again call attention 
to the nomenclatural vicissitudes of the species. First described 
by Berkeley as Botrytis destructor the same author later lists it 
under Peronospora, citing the earlier synonym, and crediting the 
combination to Caspary, probably in recognition of some manu- 
script name. Meantime Schleiden found the same species in 
Germany and figured it with a brief description, calling it Botry- 
tis ( parasitica f) 4 This forms the basis of Peronospora Schlei- 
deni Unger, which was later amended to P. Schlcideniani in De 
Bary’s revision of the group. While the weight of this authority 
has given the latter name wide usage, the older one is the proper 
designation of the species. 
Peronospora Arenariae macrospora Farl. Bot. Gaz. 9: 38. 
1884. Not Peronospora macrospora Unger. 1847 
Of the six species of Peronospora which infest members of the 
pink family three have tuberculate oospores. Two of these spe- 
cies are European, P. Dianthia De Bary being found on species of 
Diantlius, Agrostemma, and Lychnis and P. Arenariae De Bary 
on Arcnaria and related genera, while the third is an American spe- 
cies on Silcne. In 1884 Professor Farlow first called attention 
to the American species, pointing out its intermediate position 
between the two European species just mentioned and giving 
it a varietal position under the later of these. An examination 
of American material and a comparison with both of the foreign 
species has convinced the writer that the form under considera- 
tion is entitled to specific rank. While the oospores are larger 
than those of P. Arenariae they are otherwise quite similar. The 
3 Bull. Cornell Agr. Exp. Sta. 218: 149. 1904. 
4 Grundz. Wiss. Bot., ed. 3, 2: 37. f. 106. 1849. 
