MORBID AI>rATOMT. 33 



The bright color of the outer ring, as shown by the microscope, is 

 due not to ecchymosis but to the confluence of the congested papillary 

 vessels (PI. HI, fig. 2), and thus explains the sharply defined margi- 

 nate character of the patches. Their mode of extension is as follows : 

 A single papilla is first attacked and its vessels become extremely con- 

 gested (PI. Ill, figs. 2a and 2b), as in fig. 2a (of the natural size, 

 being more distinctly seen under high magnification in fig. 2b). The 

 dark spots at the apex of the papilla indicate commencing gangrene, 

 while the effused blood, stretching from it in every direction in curv- 

 ing filaments, shows the mode of attack upon the neighboring papillae. 

 As the congestion extends, the central papillae show a circle of dull 

 gangrenous appearance, the outer papillae are engorged to the highest 

 degree of vascularity, forming the scarlet-colored ring (PI. Ill, fig. 

 1,) and thus disorganization spreads from the center to the circum- 

 ference. 



The third stomach is usually full to swelling ; it is sometimes firm 

 and sometimes soft to the touch, and in accordance therewith the 

 contents are sometimes solid and dry (often so much so as to be capable 

 of being rubbed to powder), in cake-shaped layers, squeezed together 

 between the compartments, and sometimes merely damp, pappy fod- 

 der. In the former case, the mucous membranes lining the walls of 

 the stomach appear in places ragged and loose and sticking to the 

 fodder ; in the latter case, the mucous membrane is very much softened 

 and the surface skin easily removable. (Egan.) 



In some instances the purple circles so much spoken of can be ob- 

 served, but it is a state which I believe exists also in other diseases. 

 The epithelium peels off attached to the ingesta, which is found gene- 

 rally hardened between the folds, themselves injected, while the 

 papillae stand erect and prominent. (Pallin.) 



The third stomach is affected with inflammation in patches. This 

 inflammatory action often going on to a degree of intensity as ulti- 

 mately to end in ulceration. (Simonds.) In most of the cases observed 

 by J. Simon, tliere was considerably more affection of the third 

 stomach than appears to be general, according to the German reports. 

 The claret-colored patches and eventually sloughs were more frequent 

 in England.* (1st Rep., p. 43.) 



The abomason, or fourth stomach, is reddened in the earlier stages 

 of the disease only a little more than in health, but the color deep- 



* The abrasion of the epithelial membrane is not a diagnostic sign of this disease ; nor is the 

 peeling off and adhering to the plastic surface of the food to be confounded, as has been sup- 

 posed by some, with the erosion of the mucous membrane. 



The epithelium undergoes constant change in health, and can be readily stripped from the third 

 stomach of a perfectly healthy animal freshly slaughtered. (Smart.) 



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