432 



Drs. C. Shearer and H. W. Crowe. 



five minutes. A sample was spread on a film and the remainder of each 

 specimen mixed with the saline and washed three times. A further sample 

 was planted out 40 minutes after the mixtures were put up. After two 

 hours half the centrifuged deposit of mixture S in saline was crushed with 

 sterile glass powder. One and a half hours later, samples were again planted, 

 and this procedure was repeated at intervals of 6 and 24 hours after the 

 commencement of the experiment. 



Microscopic appearance of the mixtures : — 



(1) " S " mixture showed extre'hie agglutination, nearly all the leucocytes 



crowded with cocci. 



(2) " P " mixture (control), no agglutination, only a few cocci in the near 



neighbourhood of the cells. It was doubtful if any microbes at all 

 had been taken up by the leucocytes. 



Experiment 5. (See figs. 6 and 7.) 



Time. 



S* 



P.* 



I. 40 minutes in saline ... 



Area planted, quite covered. 



TJncrushed. Crushed (Cr.). 



Area planted out ! Area planted out 

 quite covered quite covered 



Covered No growth 



Covered No growth 



Very few colonies. 



Very few colonies. 



Growth discrete. 

 Covered. 



* S = Coccus S + washed leucocytes and serum S (immune). 



* P = Coccus S + washed leucocytes and normal serum P. 



In figs. 6 and 7 are shown photographs of the result of this experiment 

 after 24 and 48 hours' growth, respectively. 



Eow I, P. — Very few colonies growing owing to the loose germs being 

 washed away, whereas in S the leucocytes hold the organisms. 



Eow II. — The excellent growth in the crushed area (Cr.) shows that the 

 manipulation with the glass powder did not destroy the vitality of the germs, 

 although no leucocytes were left intact (confirmed microscopically). 



Eow III. — In column (Cr.) where crushed leucocytic deposit is planted, 

 the free germs have succumbed to the action of the saline. There is no 

 growth. On the left hand, however, where the leucocytes were intact, 

 growth was maximal. 



Eow III and IV, P. — Growth steadily increasing. We must suppose that 

 a few germs have been taken up by the leucocytes. These have probably 



