206 APPENDIX 



It is important in the haemolytic tests that all 

 the glassware be absolutely clean and dry, though 

 it need not be sterile. 



In testing for the presence of isoprecipitins, equal 

 parts of the two sera are mixed in a small test-tube, 

 the mixtures kept in the incubator for two hours 

 and then examined. 



