1904.] Production of a Specific Cfastrotoxic Serum. 137 



membrane was ground up in a glass mortar with a small quantity of 

 sterilized sand in order to break up the cells, and an emulsion made 

 with one of the above solutions. The emulsion was then filtered 

 through a Pasteur-Chamberland filter and the resulting filtrate used 

 for injection. 



The effects obtained on injecting the serum of these two rabbits into 

 guinea-pigs were exactly the same as those which resulted from 

 injection of the serum of rabbits which had received injections of 

 stomach cells. 



Collection of Blood. The blood is collected by opening a vessel of the 

 ear, if possible an artery, having first shaved and disinfected the skin. 

 In this way from 30-40 c.c. of blood can easily be obtained, without 

 injury to the animal, especially if a flask of hot water be placed in 

 contact with the ear to promote vaso-dilatation. The blood is whipped 

 and centrifugalised. 



The resulting serum- is examined : (1) With regard to its action 

 upon the stomach cells of the guinea-pig in vitro ; (2) With regard to 

 its action upon the guinea-pig's stomach when injected into the 

 peritoneal cavity of that animal. 



Examination in Vitro. My plan has been to take a scraping from a 

 fresh guinea-pig's stomach and carefully tease out the stomach glands 

 in salt solution, separating them from the submucous and other tissue 

 mixed with them. This is quite easily done by using the low power of 

 a microscope or a dissecting lens. A portion of these glands is then 

 placed in the serum to be examined, and a similar portion in normal 

 rabbit's serum, the latter being used as a control. 



The glands are examined at various periods of time up to 24 hours 

 in the fresh condition, and also after fixing with osmic acid and staining 

 with picro-carmine. In several cases small portions of the stomach wall 

 were immersed in the serum for various periods of time and finally 

 hardened, cut into sections in paraffin, and stained with haematoxylin 

 and eosin. 



Preparation for Microscopical Examination. Patches of necrosed tissue 

 with surrounding healthy mucous membrane were cut into a series of 

 sections by the paraffin method. Eight or ten adjacent sections were 

 selected from each row and fixed on slides, from six to twelve slides 

 being thus obtained from each block. The sections were stained with 

 hsematoxylin and eosin. The stomachs of twenty animals have been 

 investigated in this manner. 



(2.) EFFECTS OF INJECTIONS OF THE STOMACH CELLS OF THE 

 GUINEA-PIG INTO THE EABBIT. 



(a) Symptoms following Injection. 



The immediate symptoms in the rabbit are those of collapse, the 

 temperature sinking to about 96 , the respiration being accelerated, and 



