19171 VETERINARY MEDICINE. 677 



beef bouillon, in which various types of organisms, including streptococci, 

 staphylococci, Bacillus typhi, B. diphtheria, B. anthracis, B. tuberculosis, B. 

 abortus, B. mallei, etc., fungi, and saccharomyces, were \ised, in all cases where 

 a noticeable difference of growth was observed it was in favor of the blood 

 media. 



The medium can be used in preparing various modifications and on account 

 of its low cost and ease of preparation it is strongly recommended. 



Methods of raising a low arterial pressure, W. M. Bayliss {Proc. Roy. 

 Soc. [London], Ser. B, 89 (1916), No. B 617, pp. 380-393).—" When the arterial 

 pressure is low from loss of blood, it can not be brought back, except to a 

 certain degree, by the injection of saline solution in volume equal to that 

 of the blood lost. But if the viscosity of such solutions is raised to that of 

 the blood, a return to normal height is possible. The effect of saline injec- 

 tions is also much less lasting than that of solutions containing gum or 

 gelatin. The difference in this case is due to the osmotic pressure of the 

 colloids, by which loss of water by the kidneys and to the tissues is prevented. 

 Solutions containing gum do not produce edema in artificial perfusion of organs. 



" When the fall of blood pressui'e is due to peripheral vasodilatation, gum 

 or gelatin solutions, although more effective than pure saline, produce a much 

 less permanent rise than in cases of loss of blood. No signs of heart failure 

 could be detected and the cause of the fall of the raised pressure to its original 

 height is still obscure. The combination of a small dose of barium chlorid, 

 as recommended by Langley,* with a moderate amount of gum solution was 

 found to be the most satisfactory method in such cases and no diminution of 

 vasomotor excitability resulted. 



" The view that fall of arterial pressure produces peripheral vasoconstric- 

 tion by means of nervous channels, and that rise of arterial pressure produces 

 vasodilatation was confirmed by artificial perfusion of a limb." 



Studies in anaphylaxis, XVIII, XIX, R. Well (Jour. Immunol., 2 {1916), 

 No. 1, pp. 95-124, figs. 5). — Two studies are reported, continuing previous woi'k 

 (E. S. R., 34, p. 778). 



XVIII. The mechanism of delayed shock (pp. 95-108). — Experimental data 

 submitted show that there is, in actively sensitized guinea pigs in which the 

 circulating blood has been largely replaced by normal blood, a delayed reaction 

 on the intraperitoneal injection of antigen. Circulating antibody is not a 

 factor in the production of delayed shock, since the simultaneous injection of 

 antibody intravenously and of antigen intraperitoneally does not induce an- 

 aphylactic symptoms. " The isolated uterus effectively reproduces the picture 

 of delayed shock if the antigen is very gradually added from a burette. 



" The factors in the mechanism of acute and of delayed shock are identical, 

 namely, the reaction of cellular antibody with freshly introduced antigen. In 

 the case of acute shock the reaction is immediate, owing to the sudden intro- 

 duction of antigen, which is, as a rule, accomplished by the intravascular 

 route. In the case of delayed shock the reaction is delayed, owing to the 

 cumulative effect of the gradual absorption of antigen, as from the peritoneal 

 cavity." 



It is indicated that the gradual mode of reaction of the cells may possibly 

 explain some of the symptoms of infectious diseases. 



XIX. Simultaneous injections of antigen and antiserum. — The anaphylatoxin 

 theory of anaphylaxis (pp. 109-124). — Characteristic anaphylactic symptoms 

 have been produced in guinea pigs, in exceptional cases only, by the simul- 

 taneous but separate injection of antigen and antibody intravenously. In rab- 



»Jonr. Physiol., 45 (1912), No. 4, pp. 239-260. 



