88 PROPERTIES OF ILEMOLYTIC SERA 



first. The passing-off of the agglutination is seen both in 

 the case of the unlysed corpuscles and also in the case of 

 the stromata. 



We have also inquired into the temperature at which the 

 agglutination occurs. It is seen within a few minutes (with 

 the doses mentioned above) at 37 C. and in a not much longer 

 time at the room temperature. At C. on the other hand, 

 even after a period of two hours, there is practically no agglu- 

 tination visible to the naked eye. It would appear from 

 this that the agglutinating action of complement was absent 

 at this temperature, but if we centrifugalize the treated 

 corpuscles it is found that they adhere in masses so firmly 

 that they cannot be separated by shaking. It is thus shown 

 that there is some slight action at 0C., evidenced by 

 abnormal stickiness of the corpuscles but not by the spon- 

 taneous clumping seen at higher temperatures. We therefore 

 cannot say that the agglutinating substance is entirely 

 without action at C., though it is much less marked than 

 at higher temperatures. We may mention another case, 

 viz. guinea-pig's corpuscles, immune-body from the rabbit, 

 and ox's complement, with which combination there is 

 marked agglutination by complement at C., though of 

 course there is no lysis. 



When the ox's serum is heated for an hour at 55 C. its 

 agglutinating property, like its haemolytic, is lost, such a 

 serum having no effect when added to ox's corpuscles treated 

 with immune-body. 



From this short statement it is seen that the agglutinating 

 body, studied in the normal serum of the ox, resembles 

 haemolytic complement both as regards (a) its comparative 

 lability it is rapidly destroyed at 55 C., and (b) its acting 

 only in association with immune-body. These circum- 

 stances justify the application of ' complement } to it. It is 

 not quite clear, however, whether this agglutinating comple- 

 ment and the ordinary lytic complement are one and the 



