886 EXPERIMENT STATION EECORD. [Vol. 38 



The author concludes that a practical application of the results obtained 

 could be made in the preserving industry in the sterilization of various fresh 

 foods. 



The value of WulfE's method for the diagnosis of anthrax, L. Sani {Clin. 

 Vet. [Milan], Rass. Pol. Sanit. e Ig., 41 (1918), No. 1-2, pp. //-iO).— The diag- 

 nosis of anthrax ^yith the aid of bone marrov? as described by WulfC (E. S. R., 

 27, p. 781) is considered by the author, after experimental work, to be prefer- 

 able to all other methods, particularly where the diagnosis has to be made 

 on carcasses which have undergone extensive putrefaction. The compactness 

 and chemical composition of the bones are such as to offer greater resistance to 

 putrefactive action and a favorable place for the development and preservation 

 of the anthrax bacillus. 



Studies on diphtheria toxin. — I, Hydrogen-ion concentration and toxi- 

 cogenicity determinations with Bacterium diphtherias, L. Davis {Jour. Lab. 

 and Clin. Med., 3 {1918}, No. 6, pp. 358-367, figs. 2).— The purpose of the present 

 investigation was to determine by means of the hydrogen electrode the reaction 

 changes which take place in the medium during the formation of diphtheria 

 toxin on a practical scale, and to note the relationship between toxicogenicity 

 and hydrogen-ion concentration. The medium used for the study was plain 

 bouillon made by adding 20 gm. of peptone and 5 gm. of sodium chlorid to every 

 liter of beef infusion prepared in the usual way. Adjustment to the desired 

 hydrogen-ion concentration was made by the method of Clark and Lubs (E. S. 

 R., 37, p. 506). The experimental data led to the following conclusions: 



" Toxin of maximum potency is produced In bouillon by B. diptherice only 

 when the initial reaction falls within a certain zone of alkalinity, included 

 within the hydrogen-ion concentration limits of about 7X10'' to about 5X10'^ 

 Luxuriant growth of the organism appears to be possible where the reaction of 



the bouillon ranges from about Cg^lXlO"* to about CjJ=8.4X10-'°. When 

 cultivated in plain bouillon under optimal conditions, B. diphtheria undergoes 

 an initial increase in hydrogen-ion concentration. This is soon followed by a 

 steady decrease until apparently a limiting alkaline reaction is attained. The 

 total acid produced is relatively small and seems to vary in amount v/ith each 

 individual strain. Toxicogenic strains appeared to develop more acid than an 

 avirulent strain. The initial increase in hydrogen ions is due to fermentation of 

 some constituent in both peptone and beef infusion. No direct relationship can 

 be found between the hydrogen-ion concentration of the medium and toxicity 

 during the growth of B. diphtherice." 



The intrapalpebral mallein reaction, A, Lanfranchi {Mod. Zooiatro, Parte 

 Set., 28 {1917), No. 9, pp. 197-202. fig. 1; abs. in Rev. G6n. MM. V6t., 27 {1918), 

 No. SlJf, p. 86). — The author states that in cases where the intrapalpebral 

 mallein reaction, previously noted (E. S. R., 32, p. 874), produces either through 

 successive injections or other causes sclerosis of the connective tissue, the in- 

 jection of mallein may be made in the iipper instead of the lower eyelid. In 

 case of a negative reaction at least 15 days should elapse before repeating the 

 injection. 



The intrapalpebral reaction in the diagnosis of epizootic lymphangitis, 

 A. Lanfranchi {Mod. Zooiatro, Parte Sci., 28 {1917), No. 10, pp. 217-225, figs. 

 5; abs. in Rev. G4n. M6d. Y6t., 27 {1918), No. 314, pp. 80, 81).— The intrapal- 

 pebral reaction employed in the diagnosis of glanders, previously noted 

 (E. S. R., 32, p. 374), has been successfully applied for the diagnosis of epi- 

 zootic lymphangitis. The material for the test, taken aseptically from mature 

 lesions rich in cryptococci, is attenuated by shaking in ether for about 24 

 hours, evaporating the ether, and heating the mixture for from 15 to 20 min- 



