FIELD CROPS. 627 



fereiit variotios are widely cnltivatod and oxtonsivoly used as #ood, altli()Uj;li a 

 number of fatalities have heen attributed to their use. Descriptions of the 

 different varieties and detailed reports of the cheniical studies are given. 



Praotically all varieties of I^. ]iin(ttits, whether wild or cultivated, were found 

 to contain the principle which when acted upon by an enzyni yields hydrocyanic 

 acid. The proportion of hydrocyanic acid varied from almost iiiapitrcciablc 

 amounts in some of the more improved forms, like the Lima bean, to as mucli 

 as 60 to 320 mg. per Kio gm. dry weight in certain varieties of Java beans. It 

 was found impossible by cDoking to I'emove all the cyanogenetic compound in 

 .Java beans. I'rokmged boiling e.xtracts the greater part, but it is merely 

 withdrawn and not destroyed, and if the water is absorl)ed it presents the 

 same danger as the beans themselves, since either in the alimentary tract 

 or in the blood there ai-e sutticient ferments to act upon the dissolved glucosid, 

 resulting in the liberation of hydrocyanic acid. 



Incidental to the investigation the author discovered a new method for 

 detecting the i)resence of hydrocyanic acid in plants. It is based upon the 

 action of hydrocyanic acid in changing to a red color a mixture of picric acid 

 and an alkali through the formation of isopurpuric acid. Strips of blotting 

 paper are soaked in an aqueous solution of picric acid, dried, imju'egnated with 

 a solution of carbonate of soda, and again dried. A strii) of this paper sus- 

 pended in a test tube containing 1 or 2 cc. of liquid containing hydrocyanic 

 acid will after a time take on an orange red color, afterwards changing to red, 

 the rapidity of coloration 'depending upon the temperature and amount of acid 

 in the solution. A solution containing 0.005 mg. of hydrocyanic acid will 

 change the paper to orange red in 12 hours, and 0.002 mg. will be indicated 

 within 24 hours. 



A second Ohio weed manual, A. I>. Selry (OTiio Sfa. liuL 175. [jp. 21)l-.iS.'i. 

 fiffs. 73). — This is a revi.sed and enhirged edition of Bulletin S:? of the station 

 (E. S. R., 9, p. 10.54). 



After an introductory statement regarding the nature of weeds, methods of 

 introduction and spread, vitality of weed seeds, etc., the author gives an illus- 

 trated descriptive list of 385 species of weeds that have been observed to occur 

 in Ohio. The more obvious characters of each weed are described and illus- 

 trations presented of those which are most injurious or which have been but 

 recently introduced. Wherever possible the seed characters of the plants are 

 presented. The descrii)tive list is arranged at-cording to the plant families, the 

 connnon and scientific names being given. 



The author calls attention to the occurrence of f^jreign seeds found in various 

 samples of commercial seed, listing the species of weed seeds that have been 

 observed in red clover, alfalfa, alsike clover, timothy, and oats. 



FIELD CROPS. 



A successful hog and seed-corn farm, W. .1. Spit.t.man (U. 8. Dcpt. Arjr.. 

 Faniirrs' Bid. 272, pp. 16. ^f/.s'. 5). — This bulletin contains a description of the 

 system of management on a successful hog and seed-corn farm in Illinois. The 

 main points discussed are the general management of the farm, the construction 

 of shelters for hogs, the culture of soy beans and corn, the feeding value of 

 corn, clover, and soy ixvins. th(> rotations followed on the farm, and the financial 

 results seciu'ed. 



Forage crop practices in western Oregon and western Washington, 

 P.. IIi-XTKi; il . s. II, pi. Afir.. I'lininr.K Hiil. 211. pp. :i9, fKju. //).— This bulletin 

 is identical with I'.ur. I'lant Indus. I'.ul. '.II ( K. S. It.. IS. \). 220). 



Annual report of the Burdwan Agricultural Experiment Station for 



