DISEASES OF PLANTS. 255 



of the sycamore caused by Glo&osporlum. riervlHequtmn,' and a new dis- 

 ease of medlars caused by Monilia linhartiana. The disease of med- 

 lars is characterized by the appearance of dark brown dry spots along 

 the midrib and principal veins of the leaves. These increase in size 

 until the entire leaf is invaded. The young fruits are also attacked, 

 turn l)rown, dry, and fall from the tree. 



Smut of cereals, II. L. Bolley [NortJi Dukota Sta. Rpt. 1899, j/p. 

 W-'Bo^jig. 1). — Since 1895 the author has l)een investigating the influ- 

 ence of difl'erent dates of seeding, soil condition, climate, etc., on the 

 growth of smuts, and in the case of the stinking smut of wheat has 

 drawn the following conclusions: The stinking snnit of wheat in the 

 region of the station will grow best if left exposed to the weather in 

 the unbroken smut balls throughout the winter months. For best ger- 

 mination of the spores a condition of soil atmosphere approaching sat- 

 uration is required, while the presence of actual water in the soil is 

 detrimental. A Avide range of temperature for the germination of 

 spores has been observed when the soil conditions are favorable. The 

 best soil conditions for a high percentage of infection in the field would 

 be those which give a good growth of the wheat plant, associated with 

 a saturated soil and a daily temperature showing a minimum of 15 to 

 35° F, In conducting his test it was found that the millet smut devel- 

 oped best when the ground was too wet to produce a large growth of 

 wheat smut, and it is thought probable that each species of smut will 

 hQ found to vary in the conditions required for its development. 



The use of formaldehyde for grain disinfection has been further 

 investigated with good results. Acting upon the popular belief that 

 chlorid of lime would prove beneficial in preventing snmts of wheat, 

 the authoi" investigated the subject, but found it was without value as a 

 smut preventive. 



Potato diseases and their remedies, L. K. Jones and W. A. 

 Orton {Vermont Sta. Rpt. 1899, pp>. 151-155). — This report gives an 

 account of observations and experiments made on potato diseases and 

 their control in 189S. The season was somewhat less favorable for the 

 diseases than the preceding one, the principal injury being reported 

 from tip burn, which occurred rather abundantly on potatoes planted 

 in light soils. Plant.s .sprayed with Bordeaux mixture were relatively 

 exempt from attacks of the flea-beetle and showed little evidence 

 of tip burn. In the vicinity of the station there was little injury due 

 to either the early or late blight, although some damage was reported 

 from these causes in other parts of the State. 



Spraying experiments were conducted to test the value of standard 

 Bordeaux mixture in which the lime and copper sulphate were each 

 diluted to the proper degree before mixing, an improperly made Bor- 

 deaux mixture in which the concentrated solutions were combined and 

 then diluted to the proper strength, and a commercial Bordeaux mix- 



