666 townsend: asexual stages of verruga organism 



The beginning of the fever stage doubtless follows the extensive 

 breaking up of the schizonts in the endothelial cells of the capil- 

 laries, and coincides with the extensive penetration of the ery- 

 throcytes by the merozoites. 



The eruption, which is particularly characterized by a great 

 proliferation of vascular endothelial cells, is the direct result of the 

 extensive asexual multiplication of the Bartonella in the subcu- 

 taneous tissues. The proliferation of vascular endothelial cells 

 prevents the erythrocytes from coming in direct contact with 

 cells containing merozoites. Hence the infection of the erythro- 

 cytes is cut short, the fever subsides, and the gametes are no 

 longer to be found in the blood. Hence also eruption-tissue 

 inoculations produce no gametes in the erythrocytes of the sub- 

 ject inoculated, for the merozoites contained in such material are 

 obviously unable to come in contact, under proper conditions, 

 with the erythrocytes in the new tissues. » 



Erythrocytes can evidently become infected only during their slow 

 passage through the capillaries and while in contact through positive 

 chejnotropism with a living infected endothelial cell in situ in the 

 capillary wall. Eruption-tissue inoculations are, in a sense, 

 mere transplantations, or grafts, as proved by the fact that the 

 resultant proliferation is strictly localized. They are compar- 

 able in behavior to the grafts of carcinoma and other tumors 

 which have been effected within recent years. 



The cause which leads to localized proliferation in new tissues 

 following such inoculations appears to be purely mechanical in char- 

 acter, the new proliferation resulting from a specific irritation of the 

 endothelial cells in the capillaries of the new tissues by the prolifer- 

 ated cells thus introduced. Such new proliferation may be suc- 

 cessively repeated by inoculation of old proliferated cells into 

 new tissues. This explains the lesions obtained by Strong et 

 al. in twelve series of monkeys, which they considered due to a 

 virus resident in the proliferated tissues used for inoculation.^'' 

 But they were unable to obtain lesions by injection of a filtrate 

 from these tissues ;^^ nor were they able to cultivate the virus 



1" Ibid., 122 and table II. 

 " Ibid., 125-127 and table I. 



