1901.] PUBLIC DOCUMENT— No. 33. 73 



since 1889, when it was reported by Dr. Humphrey * as 

 found in two disthict localities in the State. This time it is 

 again reported as occurring upon greenhouse cucunil)ers in 

 two entirely distinct and remote localities, namely, Beverly 

 and Leominster, but we are not aware of its [)resence 

 during the summer on out-door cucumbers, s(|uashes or 

 melons. The fungus occurs more commonly in the south, 

 and even no furtiier remote than Ohio and Long Island it 

 has proved exceedingly disastrous to out-door crops. It is 

 surmised by Professor Selby of Ohio that it i)ersists in the 

 south and works its way northward as the season advances. 

 The notable results in Long Island, obtained ))y Stewart, f 

 in spraying with the Bordeaux mixture cucumbers aU'ected 

 with this mildew, show that the disease can be practically 

 controlled. 



The fungus appears largely upon the under side of the 

 leaf, as a downy mass, greatly resembling the downy mildew 

 of the grape. It must not, however, be confounded with 

 the common powdery mildew found so frequently upon the 

 upper surface of cucuml)er leaves. It is, moreover, more 

 disastrous than the powdery mildew, and on this account 

 should not be neglected when found. 



Russian Thistle in Massachusetts. 

 The first report of the finding of the Russian thistle in 

 Massachusetts which has come to our notice is made by Mr. 

 Wm. P. Rich.j Two plants were first observed by him on 

 a railroad bank at Dedham, Aug. 22, 1897, and since that 

 time the plants have shown a tendency to increase slightly. 

 Mr. Rich states that on Aug. 4, 1900, he found in the same 

 locality twenty plants. A few of them had spread three 

 hundred feet from where first observed in 1897. The Rus- 

 sian thistle has l)een previously reported in New York and 

 Rhode Island. 



* Ei.<;hth annual report, Massacliusctts A,i,'ricultiiral Exi)erinient Station, p. 210. 

 t New York Agricultural Experiment Station Bulletin, No. 119, Geneva, N. Y. 

 X Rhodora, Vol. XL, p. 204. 



