PATHOLOGICAL HISTOLOGY 173 



blood vessels of the muscle show no unusual degree of injury. 

 The discrete degenerated fibers we are inclined to regard as 

 the result of the vascular injuries. 



The involvement of large blood vessels in the skeletal muscle 

 is second only to that in the skin and testes; although the 

 lesions in muscle are not as striking as those in the central 

 nervous system. 



(o) The female genitalia: The breast was studied histologi- 

 cally in six cases without finding lesions. 



The uterus was studied histologically in six cases without 

 finding lesions. 



The ovaries in the sixteen cases studied were negative. The 

 Fallopian tubes in five cases studied were negative. 



(p) The male genitalia: The skin of the scrotum in the 

 fourteen cases studied shows lesions of the blood vessels cor- 

 responding in number and degree to those occurring in the 

 skin of other parts of the body. 



The prostate glands from sixteen cases studied show no 

 lesions in the blood vessels or glands referable to typhus. 



(q) The testes and adnexa: (Plate XIII, fig. 38.) Vascular 

 lesions (thrombosis) are present in the testis or epididymis or 

 both in all of the sixteen male cases studied histologically. Peri- 

 vascular accumulations like those of the skin of a prolif erative 

 nature are present in most of these cases. In five cases rickett- 

 sia can be satisfactorily demonstrated in the blood vessel lesions 

 of the testis or epididymis. 



In seven cases there was a considerable degree of asper- 

 matogenesis, evidenced by absence of spermatozoa and dimi- 

 nution in the number or complete absence of mitoses. In two 

 cases the aspermatogenesis is complete in some portions of the 

 slides and is attended by slight hyaline thickening of the base- 

 ment membrane of the tubules. These two cases were not 

 attended by severe vascular lesions. One was complicated by 

 extensive bronchopneumonia. We regard this change in the 

 testes to be independent of local lesions and to a general effect 

 of the disease. Similar aspermatogenesis has been observed by 

 one of us in epidemic influenza and by Mills in epidemic pneu- 



