90 Journal of Agricultural Research voi. vi»no. 2 



evaporated at 75° C. to a sirupy consistency or until all the alcohol had 

 evaporated and the sirupy mass was emulsified with warm water. This 

 emulsion was placed in a stoppered volumetric flask, shaken with 20 

 c. c. of chloroform, 10 c. c. of hydrochloric acid were slowly added, and 

 then it was made up to a given volume by the addition of water. The 

 flask was then placed for 48 hours in running water under the hydrant 

 to facilitate the precipitation of the lipoids in the chloroform. Filtra- 

 tion followed, the filtrate constituting fraction 2, and the lipoid precipi- 

 tate on the filter paper fraction i. The precipitate was then taken up 

 with a large volume of hot, 95 per cent alcohol, and kept on a water bath at 

 75 C, until all of the chloroform was driven off. The volume was then 

 increased to a convenient amount, and aliquot parts taken for analyses. 



The analysis of fraction 3 included (a) total phosphorus, (6) total nitro- 

 gen, (c) cellulose, {d) carbohydrate after hydrolysis, (e) ash, (/) total 

 solids; the analysis of fraction 2 included (a) dry weight and ash made 

 upon an aliquot part, (&) total sugars before and after hydrolysis, (c) 

 total nitrogen, {d) phosphorus, (e) solids ; while the analysis of fraction i 

 included only (a) total solids, (6) phosphorus, (c) nitrogen, since the total 

 weight of the lipoidal material from the two samples differed by i mgm. 

 only and since the amounts were too small to admit of accurate separation. 



The determinations of phosphorus were made upon aliquot parts by the 

 Pemberton-Neuman method described by Mathews (14, p. 893-895). 



The total nitrogen was determined upon all fractions by the employ- 

 ment of the Gunning- Arnold modification of the Kjeldahl method. No 

 determinations were made of fatty acids. 



In fractions 2 and 3 the carbohydrate determination included reducing 

 sugars, total sugars, and cellulose. Prior to the determination of reducing 

 sugars, the solution was freed from organic acids, tannins, and other sub- 

 stances capable of affecting reduction by Fehling's solution. This was 

 accomplished by treatment with lead subacetate in excess, after which 

 the solution was diluted, filtered, and saturated sodium sulphate was 

 added to precipitate the excess of lead. The clear filtrate was then di- 

 luted, and an aliquot part taken for the determination of reducing sugar 

 by the Bertrand volumetric method. The reducing sugar was calculated 

 as dextrose by the Munson and Walker tables.^ Another aliquot part 

 of the solution, a part of which had been used for the determination of 

 reducing sugars, was used upon which to determine the total sugars. 

 This was hydrolyzed by the addition of concentrated hydrochloric acid, 

 following which the solution was kept on a water bath at 69° to 70° C. 

 for 10 minutes. It was then cooled, neutralized with 40 per cent sodium 

 hydroxid, and the sugar determined as invert sugar by the volumetric 

 permanganate method. 



' Wiley, H. W., ed. Offidal and provisional methods of analysis, Association of Official Agrricultural 

 Chemists. As compiled by the comjtnittee on revision of methods. U. S. Dept. Agr. Bur. Chem. Bui. 

 107 (rev.), p. 241-251. 1908. 



