750 EXPERIMENT STATION EECORD. 



with lengths of exposure much greater than those presented under ordinary 

 conditions. 



In conclusion the author states that he considers it established that bitter 

 pit is, strictly speaking, not a disease but a symptom of local poisoning produced 

 in the sensitive pulp cells of the apple, that more than one poison may produce 

 it, and that the poisons may be derived from more than one source. 



A new leaf spot fungus on pear trees in Pavia, L. Montemartini {Riv. 

 Patol. Veg., 5 (1912), No. 14, pp. 225, 226).— A brief report is made on the dis- 

 covery by the author of a fungus causing a leaf spot disease of pears in Pavia, 

 The fungus is described under the name Hadrothricum piri n. sp. 



Grape mildew and the time necessary for infection, L. Ravaz and G. Verge 

 (Prog. Agr. ct Vit. {Ed. VEst-Centre), 33 (1912). No. 7, pp. 195. 196; abs. in 

 Internat. Inst. Agr. [Rome], Bui. Bur. Agr. Intel, and Plant Diseases, 3 (1912), 

 No. Ji, p. 1058). — It is claimed to have been shown by these experiments that 

 1^ hours is sufficient time for infection to occur by fresh conidia of Plasmopara 

 viticola in water on the lower side of the leaf. 



Treatment of chlorosis of grape, J. Vercieb {Prog. Agr. et Vit. {Ed. VEst- 

 Centre), 33 (1912), No. 23, pp. 713, 7iy/).— This is a very brief account of some 

 tentative experiments in treating chlorosis of the grape with sulphate of iron. 

 The results were encouraging and further trials are promised. 



Roncet and arricciamento, E. Pantanelh (Coltivatore, 58 (1912), No. 13, 

 pp. 399-.'i05, figs. 6). — This continues the author's previous discussion of roncet 

 (E. S. R., 25, p. 654; 26, p. 851). now noting more particularly its possible con- 

 nection with another affection of the grape, occurring sporadically in Italy and 

 known as frizzle disease. Some relations of these two abnormalities to hybridi- 

 zation of certain forms and to root pressure and transpiration are also noted. 

 A later report is promised. 



The spread of American g'ooseberry mildew in Baden, K. MtJLLEE {Ztschr. 

 Pflanzenkrank., 21 (1911), No. 8, pp. Jf'i9~J,5Jf, fig. 1 ; abs. in Riv. Patol. Veg.. 

 5 {1912), No. I'l, pp. 227, 228). — A discussion is given of the first appearance 

 in 1908 ctf Spliwrothcca mors-uvce and of its later appearances in parts of Baden. 

 It is claimed that all outbreaks originated where stock brought from other sec- 

 tions had been planted and that the spread from wind-borne conidia in summer 

 is of only local importance. 



Stem-end rot and gummosis, H. S. Fawcett {Proc. Fla. State Hort. Soc, 

 2Jt (1911), pp. Jil-52, pi. 1). — A summary account is given of the investigations 

 carried on by the author while at the Florida Station on stem-end rot, due to 

 Phomopsis, and gummosis, caused by Diplodia natalensis, previous notes upon 

 them having been given elsewhere (E. S. R., 25, p. 450; 26, p. 449). 



Some fruit diseases, J. B. Rorer {Dept. Agr. Trinidad and Tobago Bui., 11 

 (1912), No. 70, pp. 75, 76). — Descriptions are given of anthracnose of the 

 mango due to Chloeosporium mangiferw and anthracnose of the avocado caused 

 by Collctotrichuni sp. It is said that both of these diseases can be con- 

 trolled by spraying with Bordeaux mixture if the work be thoroughly done 

 and started in good season. 



Banana diseases are briefly described, the two most prevalent troubles 

 being the Panama and moko diseases. The Panama disease is believed to be 

 due to a species of Fusarium, while the moko disease is apparently of bac- 

 terial origin. It is stated that the varieties of banana subject to one disease 

 are apparently quite resistant to the other. 



Spraying cacao, J. B. Roreh {West Indian Bui., 12 {1912), No. 3, pp. 275- 

 277; Dept. Agr. Trinidad and Tobago Bui., 11 {1912), No. 70, pp. S4-36).— In 

 order to ascertain whether cacao diseases, and particularly the canker and 

 black pod rot, due to Phytophthora faberi, can be controlled by spraying, the 



