DISEASES OF PLANTS. 751 



Jonathan spot, a red leutuel spot on sovonil varieties of yellow and {.Teen 

 apples, and a green sunken spot on the varieties Ben Davis and Shannon. 

 From the first two sijots a species of AUernaria has been uniformly separated, 

 while from the third several fungi have been obtained which are to be investi- 

 gated further. For the control of the bitter rot the author has found four 

 sprayings with Bordeaux mixture necessary in case of severe infection. 



Studies of poach diseases have shown that both the bro^A-n rot and scab 

 may be controlled by tlie use of self-boiled lime sulphur. 



A study of grape diseases has shown the presence of three diseases not pre- 

 viously reported from the station, a bitter ripe rot due to Melanconium fuli- 

 tjiiHUin, necrosis or dead arm caused by Cryptosjyorella viticola, and a leaf spot 

 due to a spec-ies of Pestalozzia. 



The report concludes with an account of the cooperative work of the station 

 with spraying, pruning, fertilization, and cultivation of fruit, principally ap- 

 [►les, peaches, and strawberries. 



Methods for controlling fungus diseases of the apple in New York State, 

 1). Ri:ddick (Conn. PomoL .s'or. Proc, 22 U91S), pp. .^0-.} 6). —This is a dis- 

 cussion of apple scab and its control, also brief mention of fruit six)t, and 

 blotch, bitter rot, rust, canker, collar rot, fire blight. Baldwin spot, and sun 

 scald. 



The cause of bitter pit: Its contributing factors, together with an investi- 

 gation of susceptibility and immunity in apple varieties, D. McAlpine (Prog. 

 Rpt. Bitter Pit Invest. [Aiixt.], 2 (1912-13), pp. 22.'t, pis. 62).— In continuation 

 of a previous report (E. S. R., 31. p. 244). the author discusses the causes of 

 bitter pit and those factors which contribute to its development. From experi- 

 mental evidence it Is concluded that temperature and humidity induce bitter 

 pit. and it was found that if apples are stored at a temperature of from 30 to 

 32° F. in dry air the development of hitler pit is retarded. 



Respiration in apple leaves infected with Gymuosporangium, H. S. Reed 

 and C. H. Crabill (Ahs. in Science, n. scr., Jft (1H15), No. 1048, p. 180).— The 

 authors found that diseased leaves nniformly produce more carbon dioxid than 

 healthy leaves, various factors influencing the proces,s. 



Some effects of the brown rot fungus upon the composition of the peach, 

 L. A. Hawkins (Amer. Jour. Bot., 2 (1915), No. 2, pp. 71-81; Ahs. in Science, 

 n. ser., ^1 (1915), No. lOJfS, p. 179). — ^The results are given of several series 

 of experiments on the effect of the brown rot fungus on certain carbon com- 

 pounds in the peach fruit. 



In the experiments one-half of the peach was inoculated with a fungus 

 while the other was kept sterile under the same moisture and temperature 

 conditions. At the end of two or three weeks the different portions were 

 analyzed and it was found that in the rotted portion the pentosan conteTit 

 was practically the same as in the sound half. The acid content was increased ; 

 the amount of alcohol-insoluble substance which reduces Fehling's solution 

 when hydrolyzed with dilute hydrochloric acid was decreased; and the total 

 sugar content was decreased, while the cane sugar practically disappeared. 



[A banana disease in Hawaii], E. V. Wilcox (Hawaii Sta. Rpt. 1914, PP- 

 23, 24). — A brief account is given of a disease of banana that has been under 

 observation in Hawaii for several years, and which has been confused with 

 the Panama disease. 



An examination of infested leaves, by a pathologist of'the Hawaiian Sugar 

 Planters' Station, showed the presence of a Fusarium. and at the border line 

 between healthy and diseased material a bacterial organism was found. The 

 disease has not been reproduced by inoculation, so the cause can not be 

 definitely assigned. The most obvious symptom of the disease is the death and 



