FIELD CROPS. 729 



IlENRY (Anil, riiiiii. rf /'7///.N-.. N. scr.. 10 ( IH07). Jdii.. iip. 118-12'}). — Tlie authors 

 summarize investigations relating to the oecurrenee of cyanogenetic glueosids 

 in varieties of Pliascohis IkikiIux. Tlie claim made by some investigators that 

 in the Java beans and some other varieties of /'. Iiiiiatiis several distinct glu- 

 eosids are to be foimd is in the opinion of the authors not well taken, as they 

 I»elieve that they are merely forms of phascolnnaliii. 



Concerning' the distribution of hydrocyanic acid in the plant kingdom, 

 M. Greshokf (ArrJi. Pliariii., 2.',li (1906), No. 9, pp. 6'6".)-672 ) .— The author jire- 

 sented before the British Association for tlie Advancement of Science at the 

 meeting in 1!X)(> an account of the (listriliutinu of hydrocyanic acid in the i)lant 

 kingdom, and the i)resent iJapei' gives an historical statement relating t> the 

 discovery of the varicms glueosids and their occurn'nce in various plants. 

 Eleven different glueosids are mentioned as having been isolated, occurring in 

 34 families of jilants re])resented by S(i genera and about 200 si)ecies. 



Exi^erinients with bacterial enzyms, E. O. Jordan ( liiolof/ical Studies Ini the 

 Pupilx of Will id III 'ihoiiipso)! sciJiiirick. Boston, J!i(l6. pp. J2'i-J.'f')). — The author 

 reports studies to determine the power of certain bacterial filtrates to li(iuify 

 gelatin. A number of organisms were used in this investigation, and the results 

 of the studies are given at length. 



There was found to be no evidence that the presence of gelatin in a culture 

 medium leads to any particularly rapid or alnindant production of the specific 

 ferment acting upon the gelatin. In simiile nonjjroteid solutions of asparagin, 

 lactose, and min.eral salts, such as sodium phos]iliate and magnesium suljihate. 

 gelatinase is produced by some bacteriological species quite as abundantly, 

 although not generally so rapidly, as in nutrient broth or gelatin. 



The reaction of the culture medium is apparently without effect upon the 

 enzym production except as it affects the conditions of bacterial growth. The 

 gelatin-liquifying enzyms in a number of instances were found to endure heat 

 much better in iin acid than in an alkaline or a neutral medium. The enzyms 

 were also found to withstand heat better than the bacteria producing them, 

 and in some instances manifested their activity at temperatures consideralily 

 above the thei'mal death point of these bacteria. 



The action of formalin in hardening gelatin cultures was fVmnd to be without 

 diagnostic value for the separation of species, the hardening being dependent 

 upon the stage of digestion. 



FIELD CROPS. 



Practical farming, E. T. Shepherd {London: Crosby Lockirood d- Son, 190G, 

 pp. VIII-^l.'>'i, d(nns. l-'i). — This lx)()k discusses the principles of agriculture, the 

 improvement of soils ; manures and their uses in relation to crops ; root, fallow. 

 corn, legununous. and forage crops: permanent and temporary i)astures ; and 

 farm buildings. 



David Dickson's system of farming (Athniln. On.: CiiUirdtor Pub. Co.. 

 pp. 80, figs. 1.5). — A popular treatise on farm man.-igemeut as practiced by a 

 successful Georgia farmer. Among the more important points discu.ssed are 

 the general treatment of land, the fertilization of soils and crops, and the 

 growing of corn, cotton, wheat, potatoes, turnips, and vegetables. A chapter is 

 also devoted to fruit culture and the care of stock. 



Dry farming, G. C. Baker (Jour. Dcpt. Ayr. West. Aust.. l.'f (1906), \o. 

 0, pp. 361-363). — The methods of cultui'e to be followed in order to conserve 

 and utilize to the best advantage the soil moisture are briefly described. 



Report of the associate agriculturist, C. L. Xewman (South Carolimi stu. 

 I'pt. Hinij. pp. 23-2.5). — A bi-i( f i(']i(ii't on the woi-k of the agriculturist of this 



