292 APPENDIX 



and transferred to a sterile vessel which in turn is 

 placed in a covered desiccator containing a small ves- 

 sel of chloroform. The vapor of the latter serves to 

 inhibit any bacterial growth which might otherwise 

 take place. The dessicator and its contents are then 

 placed in an incubator at 37.5° C. for twenty-four 

 hours or longer in order that autolysis may proceed 

 at a reasonable rate. 



At the expiration of this time the autolysate may be 

 diluted with a convenient volume of isotonic saline 

 solution and centrifuged to remove suspended matter. 

 This process need not be carried out aseptically, for, 

 as stated in the text, the cytost extracts prepared in 

 this fashion may be boiled and filtered through a 

 Berkefeld filter without any loss of potency. 



Before using such an extract for any particular 

 experiment it is well to test its toxicity. This may be 

 conveniently accomplished by determining the mini- 

 mum lethal dose when injected intraperitoneally into 

 guinea pigs, as described in Chapter XI, or by direct 

 injection into the mesenteric vein of animals with 

 opened abdomen. From the standpoint of general 

 utility the former method is perhaps the most satis- 

 factory. 



Rabbit, weight 1,500 gms. Abdomen opened under 

 ether anesthesia. One drop of homologus muscle 

 autolysate (previously diluted with 10 volumes of 

 saline) was injected into the liver. This caused a 

 slight turgescent reaction. 1 cc. of the extract was 

 then injected into the gastric branch of the right epi- 

 ploic vein. This caused the onset of shock — the symp- 

 toms developing slowly in the same sequence as is 

 found in traumatic shock. Upon removal of the anes- 



