114 EXPERIMENT STATION RECORD. [Vol. 4;^ 



an ordinary Petri dish. Eadi drop is inoculated with the material from in- 

 dividual su.spec-ted colonies, after whicli a fresh drop of the lactose agar is 

 placed over each one of tlie primary drops, and the plate incul>ated in the 

 usual way. 



The determination of small amonnts of sugar in the presence of higher 

 and lower decomposition products, E. Last {Biochcm. Ztsclir., 93 (IDl'J), No. 

 1-2, pp. 66-81). — A study of different methods of removing interfering protein 

 decomposition products in the volumetric determination of glucose in biologi- 

 cal solutions is reported with the following results: 



The higher protein decomposition products (albumoses and peptones) which i 

 affect the accuracy of the glucose determination were best removed by precipi- 

 tation with mercuric chlorid in neutral solution. The presence of acids or 

 of excess of the sublimate renderetl the method inaccurate. Good results were 

 obtained on the addition of 2 gm. of the sul)limate to 1 gm. of peptone. The ■ 

 results obtained with mercuric nitrate as a pi'ecipitant were also good if the . 

 reaction was carried out carefully. Both of these reagents also remove erep- 

 tone, the presence of which interferes with the reaction. Monamino acids were 

 found to have no effect on the reaction. 



Determination of glucose in the presence of lactose, E. Hildt (Compt. 

 Rend. Soc. Biol. [Paris], 82 {1919), No. SO, pp. 1241-12Jf3)— For the determina- 

 tion of gluco.se in pathologic urines containing lactose the author recommends 

 the volumetric Fehling method after the complete hydrolysis of the lactose 

 with the use of benzene-sulphonic acid as a catalyzer, as previously recom- 

 mendetl (E. S. R., 40, p. 507). 



Studies in the heat resistant organisms of cold packed canned peas, R. 

 NoKMiNGTON {Michigan Sta. Tech. Bui. 47 {1919), pp. 33). — This bulletin re- - 

 ports an investigation of the cause of occasional .spoilage in home-canned vege- : 

 table.s. The study was conducted on 13 lots of peas canned according to the .. 

 Government methods for cold pack canning, using Mason and Seal-fast quart 

 and pint jars. One lot was heated in steam for 3 hours, 5 were cooked for 3 

 hours by the hot water bath method, and 7 were processed in the autoclave at 

 15 lbs. pressure for 40 minutes. One lot was canned the same day that the 

 peas were picked, 2 lots were kept at room temperature over night, and all the 

 others were kept in the refrigerator over night before canning. 



Within two weeks spoilage began to occur, which amounted to 50.9 per cent.J 

 of the autoclaved peas, 63.9 per cent of those cooked in the hot water bath, '^ 

 and 73.3 per cent of those cooked in steam. Of the autoclaved peas, spoilage 

 occurred in 12.1 per cent of those autoclaved the same day as shelled. 51.9 per 

 cent of those autoclaved for 40 nanutes the day after shelling, and 87.2 per 

 cent of those autoclaved for 1 hour the day after shelling. The high percentage 

 of .spoilage in this lot is attributed to the u.se of quart jars. 



Bacteriological and chemical analyses, the latter by the methods employed by 

 Falk, Bauman, and McGuire (E. S. R., 40, p. 712), were made of the contents 

 of 5 jars from each of 2 lots in which the spoilage was complete, and the results 

 obtained were confirmed by inoculating sterile peas under aerobic and anaerobic 

 conditions with oi*ganisms similar to those obtained and determining their 

 action. The morphological, cultural,, and biochemical properties are given 

 of 9 organisms isolated from the peas and the cultural characteristics when 

 grown in sterile peas of BaciUvs subtilis, B. ramosus, B. mycoides, and B. mcsen- 

 tericus rulgatus, the four species which corresponded most closely with the 

 organisms isolated from the peas. 



The organisms found were all spore-forming, all withstood from 10 to 15 lb. 

 pressure in the autoclave for from 10 to 20 minutes, nearly all converted starch 



