478 EXPERIMENT STATION EECORD. [Vol.37 



gatlon of the globulin particles around the antigen. " The degree to which the 

 aggregation or precipitation proceeds depends entirely on the experimental 

 conditions, on the relative proportions of antigen and antibody in the mixture, 

 on the nature of the antigen-containing substance, red corpuscle, bacillus, or 

 normal serum, on the presence of some third factor, a normal serum contain- 

 ing complement or conglutinin." 



The various serum reactions are thus considered to be the observation and 

 mensurement of a single reaction. It is indicated that the main phenomena 

 of the reaction are most readily accounted for by the adsorption rather than by 

 the side-chain theory. 



The influence of serum upon the staining of bacteria in suspensions, M. S. 

 Fleishee {Jour. Med. Research, 36 {1911), No. 1, pp. 31-49). — Serum added to 

 a mixture of bacteria and certain dilute basic stains (neutral red, methylene 

 blue, gentian violet, methyl green, and Bismark brown). 1 part in 25, prevented 

 the staining of the organisms. A similar although weaker action was produced 

 by using egg albumin in the place of serum, and a very weak action was exerted 

 by 3 per cent gelatin solutions. 



The addition of acids or alkalis did not interfere with the inhibitory action 

 of the other substances. The action of the serum diminished with its dimin- 

 ishing concentration, and an increasing concentration of the stain tended to 

 overcome the inhibitory action of the serum. Heating the serum or the bacteria 

 did not interfere with the inhibition of the staining. 



It is deemed probable that this inhibitory phenomenon of the serum is due 

 to a protective colloid action. 



On the cause of negative tissue transplantation. — III. The cleavage of 

 tissue protein of one animal species by the blood serum of an animal of 

 another species, A. Albankse {Atti R. Accad. lAncei, Rend. CI. Sci. Fis., Mat. 

 e Nat., 5. ser., 25 (1916). II, No. 12, pp. 50/-.505).— Tabulated data of the action 

 of the blood serum of the rat on the protein of the mouse, rabbit, guinea pig. 

 and dog ; of the blood serum of the mouse on the protein of the rat ; of the 

 blood serum of the guinea pig on the protein of the rat, mouse, dog, and rabbit ; 

 and of the blood serum of the rabbit on the protein of the rat, mouse, and 

 guinea pig are submitted. The Abderhalden procedure was used In the study. 

 The results are briefly discussed. 



The origin of the proteolytic ferments of the blood.— The question of the 

 specific character of certain ferments, L. H. Si.oan (Amer. Jour. Physiol., 39 

 (1915), No. 1, pp. 9-19). — Data relative to the action of blood serum from 

 pregnant individuals on human placenta and on various tissues (pancreas, 

 liver, and kidney) and of blood serum from normal individuals and blood serum 

 from various pathological conditions on human placenta are reported. 



From the results it is concluded that there is an increased proteolytic fer- 

 ment action of the blood serum during pregnancy. This increased activity is 

 (onsidered probably due to an increa.se in the polyvalent ferments. Normal 

 blood serum was found to have a weak nonspecific proteolytic action. Since 

 many advanced pathological conditions gave a positive reaction, it is indicated 

 that the Abderhalden method does not " provide a reliable test for the differ- 

 ential diagnosis between the strictly physiological state of pregnancy and 

 certain pathological conditions." The test is considered to be quantitative 

 and not qualitative. 



The origin of the proteolytic ferments. — II, Concerning the character of 

 certain ferments. L. H. Slo-\n {Amer. Jour. Physiol., 42 {1917), No. 4, pp. 558- 

 571). — The author has studied in detail the action of blood serum of normal 

 and pregnant dogs on human placenta, the action of blood serum of dogs injected 



