90 



«narginal vein of ear with 1 cc. of a emulsion B. para- 

 typhi A. ( mulsion A). 



Killed on April 9 the 1920 at noon (46.30 hrs after 

 inoculation). 



Autopsy was made immediately. 



Autopsy — The general colour of bo- 

 ne-marrow (femur) was red. The surface 

 fcrilliant. The consislence normal. 



Histologic Study — Sections of ma- 

 terial fixed in ZENKEH-formalin, stai- 

 ned by hœmatoxylin-eosin and fluid 

 GIEMSA. 



Under a weak power a pronounced 

 congestion of the small vessels (capilla- 

 Ties), œdema of the reticulum and 

 •íTeductiou in volume and number of the 

 îat-cells. 



The parenchyma appears to be ])oo- 

 Ter in cells than the normal; this is 

 not, however, marked. 



Areas of necrosis are not to be seen. 



Rabbit 40Î-Wei5ht 1 130 grs. 



May 5 th 1Q21— (2.00 p. m.) Leucccytes=10 550 per 

 snm3 (11 600—11 200—10 000— 9 400). 



May 6 th 192! — (1.15 p. m ) LeiJCocytes=12 800 per 

 anm' (!4 800—13 400—11 800—11 200). 



May 6 th 1^21— At 1.45 p. m. inoculated subcuta- 

 aieously with 1 loopful (2 niilligramms) of a culture in 

 •gélose of B. paratyphi A. in suspension in saline solu 

 lion and sterilised by heating in a water bath at 05oC 

 for an hour. 



May 16 th 1921— Killed, at 4 00 p. ra. by violent nar 

 cosis (chloroform^. 



One description alone will suffice 

 for tliese three rabbits, so similar are 

 the lesions found. 



The only difference is that cells 

 ^Xh pigment are found only with dif- 

 îîcully in rabbits 405 and 408 whereas 

 they are not uncommon in 4Ü9. 



Histologic Study — l'n;Ier a weak po- 

 wer the fat-cells are seen to l)e reduced 

 In size and the parts of the reticulum 

 which surround tiiem are strongly sta- 

 ined by eosin. In preparations by M.\L- 

 LOHV's pro;ess (aniüii blue) these par- 

 ís are uniiormly coloui-ed orange red, 

 giving the appearance of hyaline subs- 

 lance, whereas the remainder of the 

 reticum stains blue (oedema fluid). 



The parenchyma cells are practi- 

 cally as numerous as in normal bone- 

 marrow. 



A really evident feature of this bo- 

 ne-marrow, which agrees with BUNTING 

 and SELLING'S descriptions of the re- 

 generations of the bone-marrow, is the 

 existence of myelocytes in small islets 

 of 3, 4, 6 or 10 and more cells, side by 

 side with other different groups of hae- 

 moglobin-containing cells (groups m 

 which there is regeneration of cells of 

 the myeloid class and erythrogenetic 

 groups). 



The polymorphonuclear leucocytes 

 are also abundant and the megalocaryo- 

 C3'les are well preserved. 



Ocasionally discrete areas with ca- 

 pillary congestion are seen. 



The aspect of tliese lesions is not 

 uniform; in some places the oedema 

 of the reticulum is more pronounced 

 and the fat-cells are less voluminous; 

 the parenchyma cells, although less nu- 

 merous, show a disposition in distinct- 

 groups of cells of the myeloid series and 

 erythrogenetic cells. 



I'he bone-marrow of the ICth day of 

 immunisation shows an intense rege- 

 neration of the pc.renchyma cells, of 

 the ccells the myeloid series as of the 

 hœmoglobin-containing cells; the former 

 more numerous, however, than the latter. 



The congestion of the capi.'laries exis- 

 ts only in rare places and the œdema of 

 the reticulum is already being reabsor- 

 bed; in the immediate neighbourhood of 

 the fat-cells is found a homogeneous su- 

 bstance, staining itself in orange red by 

 MALLORY's method (anilin blue) and 

 staining strongly with eosin (hyaline subs- 

 tance?). 



14th Day of immunisation. 



Rabbit 133 A-Weight 1 750 grs. 



Jan. 19 th 1920- Leucocytes=13 2P0 per mm^. 



Jan. 20 th 1920— Leucocytes (4 00 p. m.) ; 6 600 per 

 mm3. Intraperitoneal inoculation (4 20 p. m.) of 1,5 cc. oj 

 a mixture of 2 cc. of saline solution with 1 cc. of 24 

 hours broth culture of B. paratyyhi A. 



