842 EXPERIMENT STATION RECORD. 



land April 10 yielded 12J tons and 9 tons per acre of vines, green weight, re- 

 spectively, 94 days from planting. 



A study of the degenerating influence of Porto Rican conditions on a number 

 of imported vegetable varieties started 2 years ago indicates that at least the 

 okra and beans have degenerated both in vigor of the plants and productive- 

 ness. Cultural, fertilizer, and variety tests with yautias, dasheens, and yams 

 were continued with good results. Of the yams Potato and Guinea seem to be 

 the most promising in Porto Rico. 



A test of several varieties of strawberries imported from the United States 

 indicates that this fruit is poorly adapted to Porto Rican conditions. Of the 

 eucalyiits which are being tested in low, heavy lands. Eucalyptus roMsta, E. 

 piperita, and E. tcrcticornis have been the only varieties to make satisfactory 

 growth. 



A study of the imported varieties of bananas in the station's plantings shows 

 that there are many duplicates due to the common names used in the countries 

 from which they were sent. The work with mangoes was continued along 

 previous lines. 



Beport of the government horticultural experimental fields in South 

 Holland for 1911, C. H. Claassen et al. {Versing Rijkstiiinhonwproefveldcn 

 Zuid-HoUand, 1911, pp. 96, pis. 2). — This is the usual report for 1911 on co- 

 operative cultural, variety, fertilizer, and spraying experiments with fruits and 

 vegetables conducted at different localities in South Holland (E. S. R., 25, 

 p. 642). 



Note on the dipping or warm bath method of forcing plants, S. T. 

 Parkinson (Jour. Hnutheast. Agr. Col. Wye, 1911, No. 20, pp. 361-366, pi. 1).— 

 Additional tests of the warm bath method of forcing plants (E. S. R., 25, p. 

 536) are reported. The results on the whole confirm those previously obtained. 



The kitchen garden, L. Pichenaud (Le Jardin Potager. Paris, 1912, pp. 23.'i, 

 figs. 89). — A practical treatise on amateur and market gardening. Part 1 deals 

 with the general principles of gardening, gairlen equipment, etc. ; part 2 contains 

 detailed cultural directions for various classes and kinds of vegetables; and 

 part 3 comprises a working calendar for the year. 



The production of mushrooms in quarries by the means of a pure culture 

 obtained by a new process, G. Boyer (Proc. Verb. Soc. Sci. Pliys. ct Nat. 

 Bordeaux. 1910-11, pp. '/G-SO). — The author's method of producing pure mush- 

 room spawn in a sterilized medium is described. 



The effect of manganese on pineapple plants and the ripening of the 

 pineapple fruit, E. Y. Wilcox and W. P. Kelley (Hawaii Sta. Bui. 28, pp. 20, 

 pis. 2). — The studies reported in this bulletin were undertaken in continuation 

 of previous investigations relative to the effect of manganese on pineapples and 

 of the chemical composition of pineapple fruits in different stages of develop- 

 ment (E. S. R., 25, p. 340; 27, pp. 118, 129). In addition to the chemical 

 investigations a microscopic study was made of all the different parts of pine- 

 apples for the purpose of learning the structural changes produced by the 

 presence of largo quantities of manganese in the soil and the moiiihological 

 changes which occur in the ripening of the fruit. The authors call attention 

 to the fact that anatomical and chemical findings are in striking harmony. 



The root system of pineapples was found to be very variable and particularly 

 sensitive to adverse soil conditions. In manganiferous soils the roots are less 

 extensive and have characteristic swollen tips. These swellings seem to mark 

 the cessation of the lateral growth of the roots, death and decay immediately 

 following their development. The most conspicuous effect of manganese on the 

 plant is seen in the bleaching of the chlorophyll, which first begins to fade, 

 the chloroplasts lose their organized structure, after which the color disappears 



