BUKEAU OF AJS'IMAL INDUSTRY. 515 



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mesev.tery are very much tbickeued and confluent, mottled red, and 

 Aviiitisli; the medullniy portion is couimouly reddened, the cortex more 

 Irequently jiorjjed with bh)od. The glands imbedded between the coils 

 of the large intestine are usually of a very dark red. AVhen these 

 coils are torn apart, the glands are brought to view as isolated, bean- 

 shaped bodies, their dark, blood-red color contrasting markedly with 

 the adjacent paler, flesh-colored serosa. This congestion prevails 

 throughout the gland-tissue. On section the knife becomes covered 

 with blood. This description applies equally well to the glands in the 

 region of the stomach, the paler inguinals, the bronchial, and mediasti- 

 nal glands. In chronic cases, which have lasted from three to four 

 -weeks, the lymphatics are usually large, but very pale and tough on 

 section. 



The intestinal tract is ordinarily the seat of the most severe lesions. 

 In the stoma'ch the fund ms or most dependent portion is deeply reddened, 

 often blackish in color, dcijendiiig ou the amount of extravasated blood. 

 Occasionally clots of blood are found forming a coating around the food. 

 In older cases the inflammation may be absent or replaced by isolated 

 ulcers. The duodenum is rarely atfected. The jejunum seems to enjoy 

 a still greater immunity. The ileum is less exempt from pathological 

 changes, Avhich seem to be proportional to the extent and severity of 

 the lesions found in the adjoining large intestine, which will be first 

 described. 



In cases of sudden death the mucous membrane of the large intes- 

 tine is deeply congested throughout. In a comi)aratively small num- 

 ber of cases this inflammation is limited to the mucous membrane ou 

 and around the ileo-ca?cal valve. At the base of this valve there is a 

 ])atch in which are imbedded the flask-shappd glands described by 

 Klein. The mouths of these may be plugged with mucus, and there 

 may be, in addition, yellowish points and patches ou the valve (the be- 

 ginnings of ulceration), imbedded in a livid membrane. When the largo 

 intestine is deeply congested, ])oints of blood extravasation are usually 

 present, and the redness itself may be made up of aggregations of 

 dark iJoints. Clots of blood are occasionally found among the feces, 

 which may themselves consist of altered blood. In more advanced 

 cases, jiigment spots are occasionally found in lines and groui^s. These 

 spots may be surrounded by a yellowish, necrosed border. Such be- 

 ginning ulcerations are not frequent. The black blood-clot, surrounded 

 by a zone of yellow, necrosed tissue, suggests the genesis of ulcers from 

 hemorrhagic foci, lu still older cases the dark red membrane is stud- 

 ded with dirty, yellowish excrescences or ulcers, varying Irom one-eighth 

 to 1 inch in diameter. In cases of very ])rotracted disease, the inflam- 

 matory redness of the membrane has subsided, leaving the roundish, 

 button-like ulcers upon a pale background (Plate I), or large areas may 

 be covered with a continuous, ragged mass of dead tissue. 



Lesions of the ileum are either entirely absent or limitetl to areas of 



iictiform, reddening with occasional extravasations. In the average 

 L.isc of swine plague there is an abrupt change observable when the 

 valve is slit open, the dark, injected, brownish, ulcerated membraue of 

 the caecum on the one side, the pale mucosa of the ileum on the other, 

 8e[)arated by the free border of the valve. In but three of about fifty 

 cases did we find ulceration. These are fully described in the prececl- 

 ing pages (pigs !Xos. 1U3, 140, lio). In two of these (Xos. 1-40, 145) the 

 disease was produced by inoculating and feeding i)ure cultures of the 

 bacterium of swine plague. We lay some stress upou this fact, as it 

 may eventually prove the means of distinguishing this disease from 



