Journal of Applied Microscopy. 413 



increasing density of the surrounding connective tissue. This degeneration 

 consists in a fatty degeneration of the lutein cells, followed by a shrinking of the 

 connective tissue network into a compact body, the corpus fibrosum. This 

 body finally undergoes hyaline changes, leaving a fine scar tissue, which may be 

 entirely lost in the ovarian stroma. The blood vessels are the last structures to 

 give way. 



The function of the corpus luteum is to preserve the ovarian circulation. 

 This it does by preventing not only the persistence of the dilated vessels sur- 

 rounding the unruptured follicle, but also by preventing the too rapid formation 

 of scar tissue. In the young woman this function is well performed ; but in 

 older women, with increasing density of the stroma, the circulation is gradually 

 impaired. 



Cessation of ovulation is induced, not through the disappearance of the 

 follicles, but through the increased density of the stroma, which impairs the 

 circulation and prevents the development of the follicles. 



The article is illustrated by reproductions of stained and digestion prepara- 

 tions. R. M. p. 



Mallory, F. B. A Histological Study of Mallory has made a very complete 

 Typhoid Fever. Jour. Exper. Med. 3 : 6, histological Study of nineteen cases of 



typhoid fever with the object of throw- 

 ing some light on the primary essential lesions of typhoid fever, and also on 

 certain secondary lesions which result therefrom. The essential lesions he 

 believes to be a proliferation of the endothelial cells. This proliferation is due 

 to the action of the toxin of the typhoid bacillus, the toxin being produced not 

 only in the intestinal tract, but also in the blood and organs of the body. The 

 cells, which are markedly phagocytic in character, are produced most abundantly 

 alone the line of absorption from the intestinal tract in both the lymphatics and 

 the blood vessels. They are also produced in the vessels of the general circulation 

 as the result of the general distribution of the toxin, and finally in the lymphatic 

 spaces of the body generally as the result of the absorption of the toxin elimin- 

 ated from the blood vessels. 



The swelling of the intestinal lymphoid tissue, of the mesenteric lymph nodes, 

 and of the spleen is due almost entirely to proliferation of the endothelial cells. 

 The pathgocytic power of these cells is very marked. The cells most frequently 

 devoured are lymphoid cells, occasionally red blood corpuscles, and less often 

 plasma cells or polynuclear leucocytes. In some cells ten to twenty lymphoid 

 cells could be counted. A diffuse increase of these cells is also found in the 

 mucous membrane of the intestine generally. There is also an increase of 

 plasma and lymphoid cells. 



The necrosis in the intestinal lymphoid tissue is due to the occlusion of the 

 veins and capillaries by fibrin thrombi, which owe their origin to the degenera- 

 tion of phagocytic cells beneath the lining endothelium of the vessels. 



The necroses in the liver are due to obstruction of the liver capillaries by 

 phagocytic cells derived chiefly by embolism through the portal circulation. These 

 cells originate from the endothelium of the blood vessels of the intestine and 



