172 



Scientific Proceedings (114). 



the complement-fixing substances present in the sera of syphilitic 

 patients could not be applied to specific complement fixing sub- 

 stances obtained after protein injections, in view of the fact that, 

 in the former case, the antigens employed were non-specific. 

 This has led us to study the rate of destruction by heat of specific 

 complement-fixing antibodies. 



The mode of immunization as well as the complement fixation 

 tests were conducted as indicated in the first paper of this series. 

 The tests were carried out in each case with unheated serum and 

 the same immune serum heated to varying temperatures, beginning 

 with 5 minutes at 56 degrees C. and ending with 1 hour at 65 

 degrees C. It was soon found, however, that these temperatures 

 did not lessen the antibody content of the rabbit serum, and that 

 the thermal destructive point of these complement fixing anti- 

 bodies existed apparently at a higher temperature level. 



The sera were then diluted 1-10 with saline in order to raise 

 the protein coagulation level (Eberson) and placed in the water 

 bath for 2 hours at 65 degrees C; 1 hour at 70 degrees C; and 

 y 2 hour at 75 degrees C. — without any apparent effect on the 

 antibody content. The sera were then subjected to temperatures 

 of 80 degrees C. and 85 degrees C. for 15 minutes. At the former 

 temperature the antibodies were practically destroyed, while at 

 the latter, completely destroyed. 



The fact that the so-called complement fixing antibodies 

 present in the sera of patients suffering from syphilis are destroyed 

 when subjected to temperatures ranging between 60 and 65 degrees 

 C. and that specific complement fixing antibodies withstand a 

 temperature of 75 degrees C. suggests the possibility that there 

 exists inherent biological differences between the two types of 

 antibodies and opens a suggestive field for research. 



84 (1666) 



The use of blood plasma in the imbedding or the dissection of 



small organisms. 



By GEORGE A. BAITSELL. 



[From the Osborn Zoological Laboratory, Yale University.] 



Various methods have been used in order to overcome the 

 difficulties attendant upon the carrying of a minute organism, 



