164 OMENTAL PLAGUE chap. 



blood-vessels are surrounded (perivascular lymph spaces) 

 by the continuous masses of B. pestis mentioned above. 

 This is specially shown in Fig. 77 ( x 1000) from a point 

 where the B. pestis are less densely packed, and therefore 

 recognisable as such. 



Fig. 78 represents a section through the hemorrhagic 

 mesenteric gland, photographed under a low magnification 

 ( x 20). The gland is seen surrounded by fat tissue. 

 Near the middle of the upper part, close to the capsule, 

 is an afferent lymphatic (dark) densely packed with 

 B. pestis. At the right upper angle, within the fat 

 tissue, is a blood-vessel containing masses of B. pestis 

 (dark). In several places on the inside of the capsule, 

 in situations corresponding to cortical lymph sinuses, are 

 continuous masses (dark) of B. pestis ; so also in the 

 medullary part. A good deal of the cortical part is more 

 or less necrotic, and contains effused blood (light). In 

 the actual specimens, stained double with methyl -blue 

 and eosin, the contrast between the masses of B. pestis 

 (blue) and those of blood corpuscles (pink) is very 

 striking. 



Sections through the spleen, kidney, liver, and lung 

 show not only that the blood-vessels up to their finest 

 branches are distended with blood, and contain large 

 numbers of B. pestis, but that in many places there is 

 blood effused outside the vessels between the elements of 

 the parenchyma, in which blood a great many B. pestis 

 in small and large masses are seen. The spleen pulp is 

 in many places literally packed with continuous masses 

 of B. pestis in streaks and patches. Sections through the 

 testis show the intertubular lymph spaces filled with 

 blood, and amongst this continuous streaks and irregular 



