75 



pronounced in material fixed in subli- 

 mate-alcohol than in material fixed in 

 ZENKER-formol. 



It is therefore more advantageous to 

 use both fLxing-fluids since the compara- 

 tive study of the results obtained is then 

 more instructive. 



For certain purposes (research of 

 fibrin, identification of reticulum-cells) 



1 made use of various general methods 

 (methods of MALLORY with anilin-blue 

 and haematoxylin-phosphotimgstic acid, 

 V. GIESON, etc.). 



Most of the animals were immunised 

 by intravenous injections; a small num- 

 ber b}"^ intraperitoneal or subcutaneous 

 ones. 



In one group, the animals were ino- 

 culated on the same day with the same 

 emulsion from the same 24 hours' cul- 

 ture of B. paratyphi A. 



The emulsion was made in the follo- 

 wing way: 



Emulsion A. — I prepared 10 test- 

 tubes, each one with 2 cc. of saline solu- 

 tion; in each tube I made an emulsion 

 with a loop tested for 0,002 grs. taken 

 from a 24 hours culture of B. paratyphi 

 A; the contents of the 10 tubes were 

 mixed in a flask which was then placed 

 in a water-bath at 60oC. for an hours 

 time; the contents were then shaken and 



2 cc were placed in each test-tube; 

 10 rabbits were injected in the marginal 



vein of the ear, each rabbit with the 

 contents of one of the tubes. 



In another and larger group, I inocu- 

 lated each rabbit (of the weight of 950- 

 1.5Ü0 grs) intravenously, subcutaneusly 

 and intraperitoneally with an emulsion 

 in saline solution of 24 hours' culture 

 in agar of B. paratyphi A (1 loop of 

 0,002 grs. 2 cc. saline solution, killed 

 by heating during an hour in a water- 

 bath at 65oC. The counting of white 

 corpuscles was done in an American 

 standard Haemacytometer with LEVY 

 counting chamber. 



As a general rule I made 4 simul- 

 taneous determinations of the number 

 of leucocytes, sometimes only 3 or 2, 

 making use of the average of the figu- 

 res obtained. 



The normal number of white cor- 

 puscles in the rabbit is estimated at 

 5-14.000 (GRUBER), about 9.000 (HEI- 

 NEKE), 9-12.000 (PROSCHER), 8-13.000 

 (TALQVIST). Recently PENTIMALLI, 

 examining 10 normal rabbits, reported 

 individual variations in the number of 

 white corpuscles going from 4.520 to 

 10.300 per mm3 so that he advises great 

 caution in the interpretation of slight 

 oscillations: the figure 6.876 is the ave- 

 rage he obtained. 



My researches controlled by the 

 histological examination of the bone- 

 marrow, gave the following results: 



Tatole I 



Number of tlie animal 



Weight 



Nr. of white corp. per mm*. 



Rabbit 268 

 376 

 300 

 269 



1.500 grs 16.000 



970 grs 10.697 (4 days' average) 



1.060 grs 10.600 



1.500 grs 7.400 



11.174 (average). 



After working for some time, I was 

 able to give SELLING'S recommendation 

 Its due value, for advising one to 



to observe the number of white corpus- 

 cles of each rabbit on three consecutiv© 

 days and after that only making use» 



