AGRICULTURAL BOTANY. 27 



tllizers for sugar cane, tobacco, vej?etablos, and other crops in cooperation witli 

 planters in different parts of the island in order to determine the best methods 

 of use. 



The mineral industry: Its statistics, technology, and trade during 1907, 

 edited by W. R. Ingai.i.s Wcw York and London, 1908, vol. 16, pp. X+1127, 

 pis. 5. figs. 6Jf). — As usual, this annual contains chapters on phosphate rock and 

 potassium salts, as well as on other mineral products of less agricultural value. 



AGRICULTURAL BOTANY. 



Department of botanical research, D. T. MacDougal {Caniegie Inst. Wash- 

 ingion Year Book, 7 {IDOS), pp. 55-73, pis. 4). — A progress report is given briefly 

 describing the various lines of work that are being carried on by this depart- 

 ment. Among them are studies on the general role of water evaporation in plant 

 life, the physiology of transi)iration in plants, the histology of hybrids, and the 

 effects of altitude, isolation, and other cliniiitic factors on plant growth, and 

 experimental researches on the production of new species of plants. 



Eeport of the botanist, A. Nelson (Wiioming Sta. Rpt. 1908, pp. .'i8-50). — 

 A brief report is given of the work carried on by the station botanist, which 

 included experiments with alkali and drought-resistant forage plants, tests of 

 shade trees, ornamentals, etc. 



Seeds and plants imported during the period from July 1 to September 

 30, 1908. Inventory No. 16 {U. S. Dept. Agr., Bur. Plant Indus. Bill. /.'/8, 

 pp. 37). — Tills is the sixteenth inventory of seeds and plants imported by the 

 Office of Foreign Seed and Plant Introduction and represents for the most part 

 material secured by correspondence in different parts of the world. About 400 

 numbers are included. 



Vegetation affected by agriculture in Central America, O. F. Cook ( U. 8. 

 Dept. Agr., Bur. Plant Indus. Bui. l.'fS, pp. 30, j)ls. 8).— The effect of primitive 

 agricultui'al conditions, as shown by tlie present vegetation of portions of Cen- 

 tral America, is described. 



The author states that following the repeated clearing and burning of the 

 woody vegetation for the planting of corn, the land becomes overgrown with 

 coarse grasses. The burning of these prevents tlie growth of young trees, and 

 such processes result in the denudation of the land. The alternating processes 

 of denudation and reforestation have continued in Central America for a long 

 time, and it is evident that the simple operations of cutting and burning of the 

 natural \egetation can induce desert conditions even in naturally forested 

 Iroijical I'egions. 



Studies in Trifolium, I, P. B. Kennedy (Miililcnhcrgia, 5 (1909), No. 1, 

 pp. 1-13. pi. 1). — Studies are reported on tlie species of clover belonging to the 

 Amoria section found growing spontaneously or under cultivation in America 

 noi'tli of Mexico. 



Notes on some wild forms and species of tuber-bearing Solanums, A. W. 

 Sutton (Jour. Linn. Soc. \ London], Bot., 38 (1909), No. 268, pp. .',Ii6-Jio3, j}ls. 

 12). — A report is given on investigations conducted by the author, a preliminary 

 notice of which has appeared (E. S. R., 20, p. 128). Since 1886 he has been 

 carrying on experiments with different species of Solanum to determine if 

 possible tlie si)ecies from wliich the cultivated jiotato is derived. Among the 

 species first studied were 8(dannm maglia and S. conimcrsonii. In addition to 

 these, 5 wild sjjecies (H. tuhcrosum, 8. polyadcnimn, 8. verrucosuni, S. tnherositin 

 liorealc. and N. <l iibcrosum) have been studied. Of these all except the last 

 flower freely and i)roduce fruits which contain an abundance of seeds, and 

 plants raised from the seed exhibit little or no variation from the parent plants 



