1917] HORTICULTURE. 445 



dewberries and hybrid varieties that are grown either as dewberries or as 

 blackberries can be attributed either to a nonattraction or to a repulsion of 

 the sexual elements from the same plant or from the same variety. 



The pollen from most of the self-sterile varieties will successfully fertilize 

 flowers of other self-sterile or self-fertile varieties. Fully self-fertile dewberry 

 plants and blackberry plants when self -pollinated produce apparently as good 

 fruits as when cross-pollinated. The results of the study as a whole indicate 

 that by judicious and careful selection of varieties one or several varieties 

 may be included in the fruit plantation with a reasonable certainty of a good 

 setting of fruit. In the case of partially self-fertile varieties and all of the 

 recognized self-sterile varieties of dewberries and blackberries a good poUenizer 

 is absolutely necessary. Under ordinary conditions several varieties should be 

 included in the plantation so as to secure the best possible results from cross- 

 pollination. 



The sycamore fig in Egypt, T. W. Bbown and F. G. Waxsingham (Jour. 

 Heredity, 8 {1917), No. 1, pp. S-12, figs. 7). — An account of the sycamore fig 

 with reference to its history, botany, and practices employed by the natives in 

 the culture and ripening of the fig. 



The best papaws (Jour. Heredity, 8 (1917), No. 1, pp. 21-S3, figs. 7).— This 

 article describes a number of papaw fruits and trees reported in 1916 as the 

 result of prizes offered by the American Grenetic Association for photographs of 

 the largest papaw trees and for the best papaw fruits. 



Cocos nucifera, F. W. T. Hungbhi {Cocas nucifei'a. Amsterdam: Scheltem<i 

 & Holkema, 1916, pp. XII +146, pis. 40, figs. 12). — A handbook on the knowledge 

 of the coconut palm in the Dutch East Indies, including detailed information 

 relative to its history, botany, culture, and products. 



The cultivation of limes, J. B. Hakeison, C. K. Banceoft, and G. E. Bodkin 

 {Jour. Bd. Agr. Brit. Guiana, 8 {1915), No. 4, pp. 133-142; 9 {1915), No. 1, pp. 

 4-10; 9 {1916), No. S, pp. 122-129; 10 {1916), No. 1, pp. 6-8).— A popular 

 treatise on lime culture, with special reference to British Guiana. In addition 

 to cultural details information is given relative to the control of insect pests 

 and diseases, cost of establishing a lime plantation, and preparation of lime 

 products. 



The vanilla plantations of Tahiti and Moorea, E. P. Meinecke {Les Vanil- 

 lidres de Tahiti d de Moorea. Papeiti: Govt., 1916, pp. 44)- — This embraces 

 the results of a survey of the vanilla industry in the islands of Tahiti and 

 Moorea. Information is given relative to the nature and extent of the industry ; 

 the various pests of vanilla, together with suggestions for their control ; and 

 the improvement of cultural methods. 



Germination of yerba, V. Gaein {Bol. Min. Agr. [Argentina], 20 {1916), 

 No. 7-8, pp. 568-577, fig. 1). — The results are given of some germination tests of 

 yerba mat§ seeds previously treated in different ways mechanically, chemically, 

 and by stratification. 



Yerba mate (Ilex paraguayensis), G. T. Bketoni {Bol. Min. Agr. [Argen- 

 tina], 20 {1916), No. 7-8, pp. 578-552).— A paper similar to the above dealing 

 with different methods of treating yerba mat6 seed preliminary to planting. 



The American nut industry, H. A. Gossabd {Ohio Forester, 8 (1916), No. S, 

 pp. 29-SS). — A review of the American nut industry in its various phases, based 

 largely on the literature of the subject. 



Effects of large applications of commercial fertilizers on carnations, G. D. 

 Beax and F. W. Muncie (Jour. Amer. Chem. Soc., 38 (1916), No. 12, pp. 2784- 

 2804). — This paper presents the data secured In a study of the causes and 

 effects of overfeeding with the more ordinarily used commercial fertilizers. 

 The fertilizers chosen for the experiment were dried blood, sodium nitrate, am- 



