344 EXPERIMENT STATION EECOED. [Vol.35 



crops. The old tops are removed at this period and new ones grown. It is 

 claimed by the growers that the renewed trees produce larger and better fruits 

 than the original bore at any time. A study of the performance records of 

 the renewed trees appeared to confirm the statements of the growers. Special 

 attention is called to the desirability of studying the effect of renewal of old 

 navel trees in California in conjunction with the maintenance of individual 

 tree records with reference to the time of pruning, the cultural treatments, 

 amount of fruit produced, etc. 



Ribbed Valencia sport, H. J. Webber {Cal. Citrogr., 1 {1916), No. 7, p. 3, 

 fig^ J ) , — A description with illustrations is given of a variation of the Valencia 

 orange in which the fruit is ribbed. 



Preliminary results on budding' and grafting' experiments with cacao, 

 H. VAN Gent (Medcd. CuUuurtuin [Buitenzorg], No. 5 (.1915), pp. 9, pis. 5). — 

 Budding and grafting experiments conducted in the Buitenzorg gardens are re- 

 ported. 



Method in manurial experiments with trees (Agr. News [Barbados'], 15 

 (1916), No. 366, pp. 145-147). — A brief description of methods employed in 

 manurial experiments with coconuts and cacao trees in the West Indies and 

 British Guiana. 



Manurial experiments on coconuts, 1914-15, J. de Veeteuil (Bui. Dept. 

 Agr. Trinidad and Tobago, 15 (1916), No. 2, pp. 56-66, pis. S).— This report 

 deals with the fourth year's results of manurial experiments with coconuts 

 being conducted under the direction of the Trinidad Board of Agriculture 

 (E. S. R., 32, p. 236). 



Coconut experiments, C. H. Knowles (Dept. Agr. Fiji Bui. 8 (1915), pp. 6, 

 pis. 2). — An outline is given of selection experiments with coconuts being con- 

 ducted on Viti Levu, Fiji, including notes on the methods used in selecting 

 seed nuts and brief descriptions of the varieties selected. 



Germinating coconuts, O. F. Cook and C. B. Doyle (Jour. Heredity, 7 (1916), 

 No. 4, pp. 148-157, figs. 6). — An illustrated study of the germinating coconut. 



The grafting of coffee, W. M. van Helten (Meded. CuUuurtuin [B uitensorg] , 

 No. 4 (1915), pp. 11, pis. 3, figs. 3). — Methods of grafting coffee are described, 

 and a list is given of the grafts of various varieties of imported coffees in the 

 Buitenzorg gardens in 1914-15. 



Growing melons on trees, J. E. Higgins (Jour. Heredity, 7 (1916), No. 5, 

 pp. 208-220. figs. 7). — An account of the papaya with special reference to irregu- 

 larities in sex and methods of breeding desirable types. The subject matter is 

 based largely on the work of the author and V. S. Holt at the Hawaii Experi- 

 ment Station (E. S. R., 30, p. 841). 



Top-working pecan trees, E. J. Kyle (Agr. and Mech. Col. Tex. Ext. Bui. 

 B-21 (1916), pp. 7, figs. 6). — Directions are given for top-working pecan trees 

 by using different methods of budding. 



Commercial production of thymol from horsemint (Monarda punctata), 

 S. C. Hood (U. S. Dept. Agr. Bui. 372 (1916), pp. 12).— As a result of .selection 

 experiments with horsemint (M. punctata), here briefly described, the author 

 has been successful in securing an improved form more luxuriant in growth 

 and with a higher thymol content than in the wild form. It is believed that 

 the selection work has been carried far enough to warrant the use of this im- 

 proved form for the commercial production of thymol in the United States. 

 Cultural methods for horsemint are here discus.se(l, together with methods of 

 harvesting, distillation, and extraction of the thymol. 



During the past five years areas up to one acre in extent have been grown 

 on various soils. The results show that an average production of 20 lbs. of 



