200 PATHOLOGY [Bot. Absts., Vol. IV, 



cedars, and very many cedars. The average yields, grades, and gross returns in each class 

 are shown. In comparison with the group having very few cedars, the losses in the "very- 

 many-cedars" group amount to a reduction of about 80 per cent in yield, 66 per cent in grade 

 and about 90 per cent in value. The losses in the other two classes were intermediate and 

 comparable. The loss in all classes having more than very few cedars is estimated at $7.80 

 per tree, and is thought to have exceeded one-half million dollars for the county as a whole. — 

 F. D. Fromme. 



1318. Mayer, Karl. Die Rotfaule. [The red-rot.] Forstwiss. Centralbl. 41:121-127, 

 185-195. 1919.— See Bot. Absts. 4, Entry 451. 



1319. McAlpine, D. Immunity and inheritance in plants. Australian Advisory Council 

 Sci. and Indust. Bull. 7: 78-86. 1918. — Address delivered before a conference of agricultural 

 scientists. 



1320. McKinney, H. H. Nomenclature of the potato scab organism. Phytopath. 9: 

 327-329. 1919— See Bot. Absts. 4, Entry 1128. 



1321. McRae, W. A disease of the para rubber tree, caused by Phytophthora Meadii, 

 McR. Agric. Jour. India 14:566-577. PI. 1. 1919. — The disease caused by the fungus 

 Phytophthora meadii was first noticed in 1909-10. The symptoms are an abnormal leaf fall, 

 following the preliminary reddening or yellowing of the leaves. The green leaves first show 

 dull grey spots of irregular outline with minute drops of coagulated latex towards the interior. 

 Early in the monsoon season ashy-gray spots appear on the fruit of infected trees and gradu- 

 ally cover the whole fruit. After falling of fruit the laterals die back. Usually a bark rot 

 follows. The fungus, Phytophthora meadii, is found in all tissues of the affected parts. The 

 hyphae ramify chiefly between the cells and produce sexual cells inside the tissue of the 

 fruits. The sporangia are minute pear-shaped sacks containing usually from 14 to 22 spores. 

 The fungus spreads rapidly in the monsoon season. The preventive measures are cutting 

 away of infected wood and removal of diseased fruit, or destruction of flowers to prevent 

 the formation of fruit. — J. J. Skinner. 



1322. Melchers, L. E. A method of steam sterilization of soil for controlling nematodes. 

 Phytopath. 9:294-296. 1919. — A method of sterilizing soil in greenhouses is described, by 

 means of introducing the steam underneath a wooden skeleton platform constructed of tim- 

 bers two inches thick by four inches wide, upon which the soil is piled. By proper arrange- 

 ment the soil need be shoveled only once, the platform being pulled out and placed in the pit 

 resulting from the removal of the preceding batch of soil. The method is recommended where 

 only low pressure steam is available or where the construction of the greenhouse is such as to 

 render other methods difficult to use. — J. Johnson. 



1323. Melhus, I. E., and L. L. Rhodes. A quick method of eliminating seed-borne 

 organisms of grain. Science 50:21. July, 1919. — Holding grain in formaldehyde solution at 

 50°C. as for potato scab is ineffective or destructive to the viability of the seed. In order to 

 overcome these difficulties the grain was suspended just above a formaldehyde solution (1 

 part in 240 parts water) and the temperature was raised to 98° to 99°C. The time of expo- 

 sure was shortened to 20 seconds. Under these conditions fungi in or on the seed are killed, 

 and in a majority of cases the bacteria are eliminated. The germinating capacity was not 

 injured. It is believed that the method can be made practicable for the control of scab and 

 other seed-borne diseases of grain. — A. H. Chivers. 



1324. Murrill, W. A. A polypore parasitic on twigs of Asimlna. Mycologia 11:319. 

 1919.— See Bot. Absts. 4, Entry 1136. 



1325. Murrill, W. A. A field meeting of pathologists. Mycologia 11: 308-312. PI. 15. 

 1919. — A field meeting of pathologists, botanists and farm bureau agents lasting several 

 days was held last August at New Haven, Storrs and elsewhere for the discussion of prob- 



