376 MARSHALL AND TEAGUE. 



recognize the fact that in all probability his results were so tabulated 

 simply for the sake of clearness in presentation. It would appear to us, 

 therefore, that Brack was not justified in assuming such a fundamental 

 difference in the biological reaction on the basis of such slight experi- 

 mental differences, and we are confirmed in this opinion by the fact 

 that our precipitin experiments indicate that the established laws of the 

 biological reaction hold also for very closely related serums. In our 

 hands the deflection test with anti-Caucasian and anti-Filipino serum 

 showed differences between monkey and Negro on the one hand and 

 Caucasian, Filipino, Japanese, and Chinese on the other, although we 

 could not distinguish with certainty between Filipino, Caucasian, and 

 Chinese as Brack claimed he was able to do. Hence we conclude that 

 neither the deflection of complement method nor the precipitin reaction 

 can be used with safety in medico-legal cases to distinguish between the 

 bloods of different races of men. 



A further comparison of the two methods was made with the serum of 

 rabbits immunized to carabao serum, and the results are recorded below : 



Precipitin limits ivith anticarabao serum (average of three determinations). 



Carabao, 1 to 3,000. Chinese cow, 1 to 900. 



Native cow, 1 to 900. American cow, 1 to 650. 



Goat, 1 to 150. 



The precipitin tests indicate that the native Filipino and Chinese 

 cow are equally removed from the carabao, the American cow being 

 further removed than either of these. The deflection tests gave less 

 clearly defined results than the. precipitin reaction and showed the 

 American and Chinese cows to be about equally removed from the carabao, 

 the native being still further removed. It has been shown repeatedly 

 that the antibody concerned in the deflection of complement is not 

 identical with the precipitins, but nevertheless the lack of agreement in 

 the instance cited is rather striking and indicates that the real nature of 

 the deflection reaction has not yet been fathomed. 



REFERENCES. 



(1) Marshall, H. T.: This Journal, Sec. B. (1907), 2, 343. 



(2) Wassermann, Neisser, Brack, and Schucht: Ztschr. f. Eyg. u. Infections- 

 kranhh. Leipz. (1906), 55, 451. 



(3) Meier, Georg.: Berl. Klin. Wchnsch. (1907), 44, 1636. 



(4) Michaelis, Leonor; Lesser, Fritz: Berl. Klin. Wchnsch. (1908), 45, 301. 



(5) Morgenroth and Stertz, Arch. f. path. Anat. Berl. (Virchow's Arch.) 

 (1907), 188, 166. 



(6) Marie and Levaditi : Ann. de L' Inst. Pasteur (1907), 21, 138. 



(7) Wassermann and Citron: Deutsche med. Wchnsch. (1907), 33, 1165. 



(8) Wassermann and Plaut: Ibid (1906), 32, 1769. 



(9) Landsteiner and Stankovic: Centrbl. f. Bakteriol. Orig. (1907), 44, 353. 



(10) Miihsam, Hans: Berl. Klin. Wchnsch. (1908), 45, 14. 



