l!>-<^] VKTKrjNAllV MKDrCTNH. 383 



l;ilM>r;il{)i-y froiii hliickicj,' virus sccurtMl fruiii iiatiirally ornirriii;,' cnscs of 

 lilackl(% After two vacciiuitions all calves were tested for iiiiiiiutiity afjainst 

 hlacklej; virus. Of the IG calves treated with pseudohlackles coininercial pel- 

 lets 8 succumbed to a 1 gni. test dose of blackleg virus, and of 8 nontreated calves 

 4 succxinibed. All of the 9 calves treated with true blackleg vaccine proved 

 immune to the same test dose of the virus, thus proving that the pseudoblackleg 

 t'onnnercial va<'ciiies do not immunize calves against blackleg. 



The limiting li.ydrogen-ion concentration of various tyix's of pneunio- 

 rocci, H. M. Jonks {.four. Infect. Diseases, 26 {1920), No. 5, pp. JfSr)-i,J,(), fig. 

 1). — A study of the factors inlluencing the H-ion concentration of various types 

 of pneumococci, according to the methods previously noted (E.. S. R., 41, p. 

 noS), is reported with the following results: 



"The final H-ion concentration producetl by pneumococci of various types 

 when grown in glucose broth varies, with different strains, between pH H and 

 n.O, being indistinguishable in this respect from various sti-ains of Streptococcus 

 Jieinolj/ticus of virulent tyjie. 



" The regularity with which these final H-ion concentration values can be 

 reproduced depends largely on the initial reaction, ordinary glucose broth of 

 pH 7 being useless for this purpose. None of the strains failed to grow, how- 

 ever, when the initial reaction was set at 7.6. 



" This failure to grow in broth of pH 7 does not account for the often observed 

 failure to secure growth of the pneumococcus when blood cultures are being 

 made, since the addition of 2 per cent of whole blood renders the medium of 

 pH 7 even superior to glucose broth of pH 7.6 in stinnilating growth. A 

 marked increase in tolerance toward the H-ion is also observed, as is also the 

 case with S. hemoJi/ticiis.'' 



Acid production by Streptococcus viridans in mediums of different 

 liydrogen-ion concentration, L. G. Grace and F. Hiohberger {Jour. Infect. 

 Diseases, 26 {1920), No. 5, pp. 451-456). — A broth having an initial reaction of 

 pH 0.8 was found to favor a more rapid growth of S. viridans, while a broth 

 having a reaction more alkaline than pH 7.6 distinctly retarded growth. No 

 appreciable difference in growth was obtained between the 5 per cent ascites, 

 0.2 per cent glucose, and 1 per cent glucose broth. 



Observations on tlie recent e|»ideniic of foot-and-mouth disease at the 

 Iloyal College of Animal Husbandry at Resgio-Emilia, A. Cihsnini {Indus. 

 Latt. e Zootec., 17 {1919), Nos. 11, pp. 103, 104; 12, pp. lit, 118; IS, pp. 127, 

 128). — The author describes three outbreaks of foot-and-mouth disease occur- 

 ring in October, 1918, and January and April, 1919, resiiectlvely, and presents 

 data to show that although the disease passed from a benign to a severe form 

 in the succeeding epidemics the animals which had recovered from an attack 

 during an earlier epidemic proved, with few exceptions, to be immune to the 

 later attacks. 



The injection into the swine of an autolyzed anti-foot-and-mouth vaccine 

 proved efficacious, the nrortality during the later epidemic being greatly reduced. 

 It is suggested that although the disease takes a somewhat different course 

 in swine than in cattle the former are better adapted to experimental study of 

 the disease from the standpoint of imnuinity, owing to their rapidity of rcpro- 

 ductiou which allows a study through several generations in a comparatively 

 short time. 



Ulcerative lympliangitls {Rev. CCn. MM. Vdt., 28 {1919), No. 329, pp. 233- 

 2.',3; also in Jour. Vompar. rath, and Tlier., 32 {1919), No. 2, pp. 127-132).— 

 Thi.s is a summary of reports of investigations of ulcerative lymphangitis con- 

 ducted by Boquet at the Alfort Veterinary School. 



