203 
that tlie size and color differences may be due to age, but in the P. violcc 
proper the spores are ellipsoidal, while in the other they are nearly per¬ 
fect spheres. No oospores have yet been found. Whether it proves 
to be the same species or not, and that can be settled probably by cul¬ 
tures, the fact remains that one of our choicest of liot-bed plants is at¬ 
tacked by a mildew that from its destruction attracts the attention of 
the violet grower and should be treated with fungicides. A weak solu¬ 
tion of the ammouiacal carbonate of copper would be likely to prove au 
effective remedy. 
Among the species of cystopus, all of which have been abundant, 
only one need be mentioned here. The search, among students of this 
genus, for the oospores of Cystopus ipomoece-pandurance , Schw. (C. Con- 
volvulacearum , Otth.) upou wild sweet potato, or Man-of-the-Earth 
(Ipomcea pandurata ), a miserable weed with enormous roots, has been 
prolonged and was rewarded only recently, as stated by Dr. Farlow in 
Botanical Gazette for August, page 187. This fungus was abundant 
in some parts of the State this year, doing valiant work in helping to 
destroy a pest in cultivated grounds. In some cases the enlargements 
of the stem where the oospores are borne in great numbers were many 
times the normal size. The particular point, however, in mentioning 
the species here is to announce that the leaves were found distorted, 
and in these thickened points the oospores abound. 
It may be said inclosing, that strange distortions of the flower stalks 
of wild mustard were met with this season, which were due to the 
growth within of another member of the same genus as above men¬ 
tioned. It also works striking modifications of the flowers and fruit of 
the cultivated radish, which are often observed by truckmen who let 
this plant go to seed. 
PREVALENCE OF ERGOT IN 1889. 
By Erwin F. Smith. 
Claviceps purpurea, (Fr.) Tul. was unusually prevalent along the east 
shore of Lake Michigan in the summer of 1889. At South Haven and 
St. Joseph I saw it in every rye-field, and it was so abundant that it 
could be gathered by the handful. Even scattering patches of rye in 
orchards, meadows, and along roadsides were infected. The best de¬ 
veloped sclerotia were two inches long, but where a half dozen or more 
grew from one head they were smaller. In that part of the country it 
has been customary for some years to grow rye in the peach orchards 
as a green manure. It is sown in the autumn and ploughed down in 
the spring, but some portion of the crop always escapes the plow and 
comes to maturity. Moreover, through neglect or for other reasons, 
the rye is not always turned under green, so that the soil may be 
