1890.] PUBLIC DOCUMENT — No. 33. 227 



tioned, spread rapidly, l)ut not with perfect regularity. 

 When the leaves and stems were mostly killed *by the 

 fungus, the fourth day after its appearance, those on sec- 

 tions 1 and 14, the third row of section 6, and the second 

 and third rows of l)oth 7 and 13, were still fresh and com- 

 paratively unharmed. Comparison with the table given 

 above shows that the sections which suffered least were 

 those in which the potatoes were planted directly on manure, 

 and the rows which were planted with the varieties desig- 

 nated as white and black. That some varieties are less 

 susceptible than others to attacks of the rot, has been 

 repeatedly shown ; but why planting on manure should give 

 protection against it, as seems here to have been the case, 

 is not easy to see ; yet there was no other difierence in 

 conditions Ijetween plots 1 and 14, on one hand, and 2—4, 

 9-11, and 15-16, on the other hand. Yet all the latter 

 sufiered equally and very severely. The attack was not of 

 the most violent sort, and, even on the worst-affected 

 plants, there was not the complete collapse into a slimy, 

 putrescent mass, which is the result of the extreme form of 

 the disease. Nothing now remained to be done but to har- 

 vest the potatoes as quickly as possible. Press of other 

 farm work prevented immediate attention, but they were all 

 harvested before the end of the month, in very good con- 

 dition, so far as the rot Avas concerned. Later potatoes, 

 on other lields, which received less prompt attention, were 

 an almost total loss. 



Notes on other fungous diseases are reserved until more 

 complete data can l)e accumulated concerning them. 



4. JV^otes on Material referred to tlie Department. 



Some of the examinations which have been made by the 

 department, of specimens referred to it, may be of sufKcient 

 general interest to warrant a Ijrief discussion here. 



1. FuiKjus in Cellar. — In Decemlier, 1888, a (juantity 

 of a white, llocculent substance, mixed with gravel from the 

 cellar bottom on which it had grown, was sent in for exam- 

 ination. The house from whose cellar the material was 

 taken was a tenement-house, and the white growth in ques- 

 tion was a source of alarm to the tenants, who threatened to 



