fs (eso. Rytec HE f peices ee ca? te eG eigen? re ~>* ee OE ee A ee | < BS ay ue is Yates ae? if . co ‘ BSA PSS LORE iy RIAN i v FAR OEM Abies iB Bete KAY i} Ay Rents (tae ay 4 4f os i is : ts 4, chan) Bie ue i ACS ats Or ribs bes Sei A eres CA eee ‘ ee ai i a i i i i i i ta “a > : 32 - - =: u 2 ’ oa vw Te es im =~ siiedandeiita beaten wets athe CORR > bce ry. tis res U.S. DEPARTMENT OF AGRICULTURE. BUREAU OF ANIMAL INDUSTRY. SPHOCIAL REPORT ON THE CAUSE AND PREVENTION (OF SWINE PLAGUE RESULTS OF EXPERIMENTS CONDUCTED UNDER THE DIRECTION OF DR. D. E. SALMON, CHIEF OF THE BUREAU OF ANIMAL INDUSTRY. BY THEOBALD SMITH, PH. B., M. D. ’ PUBLISHED BY AUTHORITY OF THE SECRETARY OF AGRICULTURE, Be eG Gee WASHINGTON: GOVERNMENT PRINTING CFFink, 1891. an TABLE OF CONTENTS. MGULOL Ol URMSIONG Ako eeicie oan ec a ~sinalssiaa! Saale emo asl o-~ vow cisincicne ce ces cosa Investigations concerning the nature and etiology of swine plague............ LENTROCIOUO A sSeson cobopa bo 6hc0, JOO COR TENH UNDHOS HaLHOS DEO beDOnseS scdaDeeanaor Brief description of the methods employed in the investigations..-........... Brief summary of the earlier investigations of swine plague (1886-1888)... __.. JiR TWO 66s0Sb 8606 coco SacoUdsn bade CHS EUD Coo b Coed DOoM GeOnMScue eSunee See Lie WonyGh (Uusils)) cons coadiboce secs hoop cage Seco neeoo SeuGEOr pene csacualcere: HngihenWiscric tot Colum Aes cs soclaces coc e cel Soa ee os eleccteltoe lin Wb iad pitiless 4, 6685 coda eS os Op AB OOD Op EERE D Rano A DOpeE CODER E aE Noe aires Uy Li ticle) Bae EAR n 6 SeCRS CHE EO COr ESR AOO EEC ROOD HOSED ae mc Sorta ali Investigations of 1889-1890. .........---. 222-222 eee eee eee eee gee ee eee eee IngchewDistrictiot Columbiaesmarc cic cmecccls see aee qeiceee see ve cia wos. See WN Gwe) CUSO Vga ssaetoasatsee sioate ce ol o cles slo consis aisiic setsle wis ie Seclnasieeeate one Swine-plague bacteria, general characters.........------ 22+ cee eee sec een cannes RESIStall COnmOpCcSULUCULVOLAaP ON iSeete tare asec es icc seit riainicc seis eee nee Pathogenic action of swine-plague bacteria.... ..---. 22+. oe eee eee enn ne Effect on small animals.....---. eee nee BBotEEseods ee eae Saati The disease in swine as produced _ the inoculation of cultures ...-..-... Swine! plague as Opseeved-in-GpiZOOLICS = — cc... soc. -cjeres secees oe - sce Disease of the digestive tract in swine plague......-----...-.--......-... Attenuated swine-plague bacteria in sporadic cases of pneumonia, in septic diseases of swine, and in the upper air passages of healthy swine and other OM CHIGALEUL ATM a Sate a tee hs jae aaclaat cases on soo scam ca ceemeectieseces Other investigations of swine plague ......--..- SSO COR MECCIO OR EEC EHO SEECEe [NTR TOD .c SES80. 0 SAGO SUC D SONOS ONES DEDADEGS Coca RAC COCRESSer ae Soee tle ERUITO PCa Meeemteteeet wee eete ate ace slats eben aiwale steiner ciapaeiosiae eee ce telomerase ERUCuIC TO DSELVaulONSmese sta mels acl Sete yee oie cite can Speiei-\= sass ore /e eiocte eis owraaperae 1. Conditions which may favor and oppose outbreaks. ........-.---- 2-2. 2. Distribution and transmission of swine-plague bacteria........ 2... --.- 3. Relation of hoe cholera to swine plague.--. -2-..2----. oese occ nae eee ee 4. Relation of swine plague to diseases of other domesticated animals ---. 5. Measures to be taken in the prevention of swine plague.....-.....--.-. (OOO S Wh Asha Ccots JoHOnS SSeS BODE Ter BOSE DOSES SEED nUInC cS AGH conten. AtSenees Appendix.—-The presence of septic bacteria probably identical with those of swine plague in the upper air passages of domestic animals other than SWAN CMD YP OTS VPA MOOTOsanoeettcicee cresccicice cclesee ae saci eee cc eae sae DASE RI VEIN Of DEALER Some oacls om side vc Sesis cclee cele ss ahaa noes seicate etiam Lica cc se 3 IPGATE 10 Ill. Ve We WA VII. \IDUE IX. X. XI. XII. LIST OF ILLUSTRATIONS. Page. Normal lungs of pig, inflated, lateral surface ....................--- 163 Samevlungs; diaphracmatic surface) -5-- 2. ---.2---s2-s0- sec-5- sce 163 Hepatization of lung with pleuritic exudate...........-.......----- 163 Same lung with adherent portion of diaphragm .....-..-.-..----.-- 163 Hepatization of lunes with necrotic (oct 2... ss... s.s ee secs c-sss 163 Pneumonia, pleuritis, and pericarditis produced by inoculation of SWAING-PlICUOwDACUCLIA seme oclansor~ teevasciaieicte es siafoisi teins eosin Selerelors 163 Caseous degeneration of lungs in swine plague.......-....----.---- 163 Caseous masses in lung tissue. Masses of exudate in large intestine. 163 Collapse and broncho-pneumoniane-n. = sch Sh Pigs. deaths temarks. No. 406 |Feb.1....| Intestinal ulcers. No. 403 |Feb.16...| Ventral lobes of jungs diseased ; croupous inflammation of large intestine. No. 405 |Feb. 18...) Extensive pneumonia and pleuritis; croupous inflammation of large intestine. No. 402 |Feb. 19. ..| Slight pneumonia; croupous inflammation of large intestine. INO a0 Suerte. Sem Not affected. As regards the bacteriological examination the following may be said: No. 406. None made because disease supposed to be hog cholera. No. 403. None made for same reason. No. 405. Swine-plague bacteria found in lungs; other organs not examined. No. 402. Bouillon cultures made from pleural shreds, spleen, liver, and biood. Gelatine cultures made from blood and liver. Nearly all the cultures from No. 402 contained a large spore-bearing bacillus which I have frequently found since then in cases of swine dis- ease having hemorrhagic lesions. Cultures from the liver and blood contained also swine-plague bacteria which were isolated by rabbit inoculation. It will be noticed that in the later cases, Nos. 403, 405, and 402, the large intestine was the seat of a peculiarly intense inflammation, ac- companied by the exudation of circumscribed masses of fibrin easily lifted away from the mucosa, leaving a paler, slightly depressed spot showing no necrosis of tissue. In the rectum this exudate formed a continuous sheet also easily removable. It might be claimed that the feeding of a dose of aloes or salts may have caused this peculiar intestinal inflammation. This claim, however, is effectually disposed of by case No. 407. This animal, one of the same herd, had not been taken from the neighboring farm. It was found dead February 22, and brought to the Station for examination. The notes of this case are reproduced because it must be considered the most trustworthy of all. No. 407. Pig of medium size, white ; skin of abdomen, chest, neck, and back deeply reddened. Fat abundant, slightly reddened along’ the linea alba. Superficial inguinal glands slightly enlarged; spleen dotted with elevated blood-red points.* * These points are found in spleens of healthy swine. 25 Stomach and duodenum normal, the latter bile-stained. In ileum Peyer’s patches are visible as groups of small, dark dots; no swelling. Mucosa of cecum and upper colon of a dirty blackish color, probably pigmented. A few hematomata beneath mucosa. Besides the diffuse pigmentation the mucosa is sprinkled with isolated or confluent masses, about one-eighth to one-fourth inch in diameter, of a dirty grayish- yellow color, loosely adherent to the membrane. When pulled away a slightly depressed surface is exposed. Much of this mass can be easily removed by simply moving the scalpel over it. There are several ulcers in the cecum with decided loss of substance. The patch of mucous glands at the base of the valve is also converted into an ulcerated mass. Lymphatic glands in abdomen slightly swollen and red- dened. Kidneys deeply reddened to tips of papill. On opening the thorax the lungs did not collapse, and a rather disagreeable odor was perceived. As in No. 405, the ventral and cephalic lobes of both lungs were consolidated. The hepatized regions were very hard to the touch, bright red, with yellowish points sprinkled in regularly. (See Plates m1and Iv.) The right lung was adherent to chest wall over the hepatized portion. A whitish, spongy mem- brane was interposed, about one-eighth to one-fourth inch thick, inclosing a small quantity of turbid liquid. On removing the lungs the membrane remained adherent to the pulmonary pleura, and was removed with difficulty. A portion of the dia- phragm was also firmly attached. The left lung adhered firmly to the chest wall in two places, where it was consolidated. The costal pleura was deeply reddened, owing to the injection of a close net-work of minute vessels. Trachea and bronchi filled with whitish foam, On section, the consolidated region is sharply but irregularly marked off from the normal tissue, very consistent and slightly elevated. The color varies from a bright red to a grayish red. In all, minute grayish points are present one-twelfth inch in diameter, about the same distance apart, and of a hazy outline. The smaller bronchi are filled with a purulent fluid. In the surrounding lobules in which the disease is more advanced the interlobular tissue is distended with a serous infiltration; the large vessels are filled with very consistent dark clots. Heart rather large, pericar- dium free; right auricle, ventricle, and large veins distended with clots; small white clot in left ventricle. Microscopic examination of the lung tissue in cover-glass preparations shows the presence of numercus bacteria with the polar stain in recent lesions; in older ones they are rare. Other forms are present, but only in small numbers. The pleural exudate was made up of rounds cells, bound together by bundles of fibrin; it con- tains few bacteria. In transverse sections of the large intestine, where a mass of exudate is still attached, the muscular and submucous layers are intact, if we except a slight cellu- lar infiltration near the base of the crypts. The mucous layer, however, is consider- ably changed. The surface epithelium, including a portion of the erypts of Lieber- kiihn, is no longer distinguishable, but merges without demarcation into an exudate several millimetres thick, consisting of leucocytes imbedded in a mesh-work of fibrin, the whole refusing to stain. Pure cultures of swine-plague bacteria in tubes of gelatine were obtained from the pleural exudate. In each needle track a large number of colonies developed. A piece of false membrane gave the same result. Cover-glass preparations from spleen and liver were negative. Two tubes of beef infusion into which bits of spleen had been dropped remained sterile. Two similar cultures from the liver contained each a large bacillus, evidently of post-mortem growth. The blood from the heart was also free from bacteria, for two tubes of gelatine, each inoculated six or seven times with blood, did not develop a single colony. A rabbit inoculated in the ear with a bit of lung tissue died within 4 days. There was no swelling or reddening of the ear. Lungs deeply congested (hypostatic?). Immense numbers of swine-plague bacteria in blood, spleen, and liver. Cultures 26 from blood and liver contained the same organisms. A mouse inoculated with a bit of lung tissue succumbed within 2 days. Bacteria very scarce in body. Pure cultures of swine-plague bacteria were, however, obtained from heart’s blood. What is of importance in this case and in No. 402 is the absence of hog-cholera bacilli from the internal organs where we would certainly expect to find them in this disease. If we refuse to consider the intes- tinal lesions as caused by swine-plague bacteria, we have the alter- native of assuming the existence of bacteria which produce intestinal disease without penetrating into the internal organs proper.* Five other cases in this investigation deserve special attention. Nos. 408, 409, and 410 of the same herd still remained on the farm. After the examination of 407 had shown the absence of hog cholera, and the presence in the diseased lungs of swine-plague germs, and the evidence thus far obtained pointed to a different disease caused by the latter bacteria, two pigs, Nos. 359 and 360, were taken from the Station to the farm and penned with the three mentioned to determine whether the disease is readily communicable. This was done February 28. March 5, No. 408 died. March 16 the remaining four were taken back to the Station and placed in an unused pen free from infection, so as to be under observation. Of these four pigs No. 409 died March 20, No. 410, March 29. Of the exposed animals No. 359 died March 24, 24 days after the commence- ment of the exposure; No. 360, April 6, 37 days thereafter. Of these four cases No. 360 was not examined. Of the remaining three, hog- cholera bacilli were detected in 409 by rabbit inoculation, but not in either 408 or 410, while swine-plague bacteria were found in 408 and 359. Looking over the original notes I am convinced that the number of cultures made from the spleens of 408, 410, and 359 were sufficient to enable us to exclude the presence of hog cholera from these cases. No. 409 is therefore the only animal from the adjoining farm which was ex- amined in which hog-cholera bacilli were detected. It is likewise strange that in the spleen of No. 408 a bacillus should appear resem- bling hog-cholera bacillus in many respects, but not identical with it, and producing only suppuration in rabbits. The cases which came under observation subsequently, and in which hog-cholera bacilli were readily demonstrated in the spleen, were Station pigs which had been exposed some time ago to the infection of hog cholera. These cases are chiefly valuable in pointing out that the swine- plague bacteria are transmitted from animal to animal and associated with lung disease. They may be thrown out altogether, since the source of the hog-cholera bacilli is traceable. No. 372. Fed viscera of hog cholera case December 24, 1886, in infected pen. * By “internal organs” I mean those organs which do not come in contact with the air or food, either directly or indirectly. Thus the entire respiratory and digestive tract may be regarded as external, so far as bacteria are concerned. ee ew eee 27 No. 378. Fed viscera of hog cholera case November 18, 1886, in in- fected pen. Fed viscera of 406 February 2, in infected pen. No. 392. Inoculated with swine plague bacteria (lowa) January 25; placed in the infected pen March 28, No. 397. Fed viscera of 378 in pen 7 March 24. In 372, 392, 397, both hog cholera and swine plague bacteria were found. Their presence in the old infected pen or their contact with pigs kept there will account for this doubie infection. The facts brought out by this investigation corroborated those al- ready brought out in the investigations of the preceding year. They showed the existence of pneumonia and pleuritis, together with intesti- nal disease in most of the animals examined, associated with bacteria readily distinguished from hog-cholera bacteria. They also demonstrated the transmissibility of the pneumonia to other pigs, and in these pigs the same bacteria were found. If the lesions of the large intestine, as observed in the early cases, were due to hog-cholera bacilli, why were these bacilli not found ex- cepting in one late case in which there may have been an accidental infection of the rabbit inoculated? Why were hog-cholera bacilli read- ily detected in the later cases kept in the infected pen ? While these investigations do not prove that the swine-plague bac- teria were the cause of the intestinal lesions, they also do not seem to show any relationship between these lesions and hog-cholera bacilli. This question of the relation between intestinal lesions and swine- plague bacteria will be discussed farther on.* V. In September, 1885, an outbreak of swine disease near Baltimore, Md., came to our notice. Three pigs from one herd and one from another herd were examined. The following synopsis of the cases may be of interest, the full account being given elsewhere.t Pig No. 1. Broncho-pneumonia; exudate on mucosa of rectum and lower colon; swine-plague bacteria detected in lungs and rectum; hog- cholera bacilli in spleen. é Pig No. 2: Three-quarters of both lungs hepatized; ulcers in ileum and colon; swine-plague bacteria in lungs; hog-cholera bacteria in spleen. Pig No. 3: Extensive pneumonia and pleurisy; ulceration of large intestine; swine-plague bacteria in lungs; hog cholera bacteria in spleen. Pig No. 4: Slight atelectasis of lungs; ulcers in large intestine; swine-plague bacteria in large intestine; hog-cholera bacteriain spleen. Pig No. 3 was taken to the Experiment Station, where it became the starting point of a mixed outbreak of hog cholera and pneumonia. bod Fo Ap t Report of the Bureau, ete., 1887-’88, p. 121. 28 VI. During November, 1888, the writer was directed to make some in- vestigations in Iowa,* where swine diseases at that time were prevail- ing to a considerable extent. In the vicinity of Mason City pigs from three herds, some distance apart, were examined. The lesions observed were both intestinal and pulmonary. The intestinal lesions, though varying considerably in appearance and intensity, did not differ, on the whole, from those observed in hog cholera. The lung lesions varied considerably in character and extent, from a slight collapse in a single lobe to almost total hepatization, accompanied by exudative pleuritis. The investigations were limited to post-mortem examination and cultures from the spleen. From each spleen small bits of tissue were removed to two tubes of agar. In addition, portions of diseased lung tissue and ulcerated mucous membrane from the large intestine were cut out and transferred to sterile test tubes plugged with cotton wool for inoculation into rabbits. Ten pigs were examined in this manner. In but one case did the spleen pulp show any bacteria under the microscope, and in this case they were streptococci. [n but one agar tube of the spleen series did anything develop. This was a motile bacillus, resembling the hog-cholera bacillus in form, but differing in its growth on agar, in bouillon, and in gelatine, this growth being in all cases more vigorous. Of two mice and one rabbit inoculated, one mouse died in 5 days. The lesions were indefinite and did not point to hog cholera. Moreover, the other mouse and the rabbit remained unaffected. With particles of diseased lung tissue and mucous membrane from some of these cases a considerable number of rabbits and some mice were inoculated. Of those that died some contained no bacteria of any description. Those inoculated from three cases out of ten died of swine plague since these bacteria were found. A few survived the inoculation. The nature of this disease was not, therefore, cleared up by these in- vestigations, since the results were not uniform. While in hog chol- era the bacilli are present in the spleen, and readily obtained therefrom by cultivation, they were not present in the spleens of these ten cases. As already stated, swine-plague bacteria were obtained from three cases. They were quite virulent, as the inoculations upon pigs show. Thus one pig, which received 9 cubic centimetres of a bouillon culture into the right lung through the chest wall; died within 20 hours of septi- cemia, the injected bacteria being present in the spleen in considerable numbers. Another pig, which received a subcutaneous injection at the same time, remained well. Somewhat later two pigs received into the right lung 14 cubic centimetres and 3 cubic centimetres of a bouillon * Report of the Bureau of Animal Industry for 1887~88, pp. 135-145, where a de- tailed account of this work is given. 29 culture. The one which had received the smaller dose was sick for a time, but recovered. It was killed 14 months after the inoculation, and both lungs were found everywhere adherent to the chest wall. In the pericardial sac a considerable quantity of pus had collected, in which the injected bacteria were still present, as determined by cultures. The animal which had received the larger dose became very ill and was killed 5 days after inoculation. At the autopsy were detected par- tial hepatization of the right lung, with extensive exudative pleuritis and pericarditis. The two following cases, which have not yet been published, demon- strate very strikingly the virulence of these bacteria. The growth on a number of agar cultures about 9 days old was scraped off and trans- ferred to sterile bouillon until a turbid suspension was obtained. This suspension was prepared because these bacteria multiply very feebly in bouillon, and when the latter is used as the injecting fluid very few bacteria are actually introduced into the body. ‘This turbid suspension was used to inoculate 2 pigs. No. 120 received into the abdomen 2 cubic centimetres; No. 143 into the right lung through the chest wall but 1 cubic centimetre. The inoculation was made March 11, 1889, over 3 months after the bacteria had been obtained from the diseased swine. No. 120. Essex female, 5 months old. Into the right lung through the chest wall, 2 cubic centimetres of above suspension injected with hypodermic syringe, 6 p. m. March 11. Found dead early next morning. Subcutaneous inguinal glands partly hemorrhagic. From the cut subcutaneous vessels of right side liquid blood oozes out. In abdomen the solitary follicles of large intestine appear as bright red circular spots three-sixteenths inch diameter, as seen from serosa. Spleen slightly engorged. Large quantity of blood-stained serum in right pleural sac. The needle had pune- tured the convex surface of principal lobe, where there was some infiltration of blood. A thin layer of fibrin on convex surface of the small anterior lobes and on pericardium. A few collapsed lobules along free border of these lobes. In stomach, the mucosa of fundus is deeply reddened over an area of 3 to 4 square inches; in this area two hemorrhagic spots. The upper half of duodenum with mucosa intensely reddened. Contents somewhat blood-stained. All Peyer’s patches in the small intestine from duodenum to ileo-cecal valve are intensely reddened, the follicles appearing as blood-red points. On some patches, hemorrhages on the surface. Considerable number of ascarides in small intestine. In large intestine the lymphatic patch near valve likewise reddened. Mesenteric and mesocolic glands hyperemic. Kidneys very much congested. The glomeruli appear as minute blood-red points. Small quantity of urine in bladder loaded with albumen. Blood fails to clot. In the spleen large numbers of swine plague bacteria. No. 143. Essex male, 5months old. Injected into abdomen 1 cubic centimetre of turbid suspension of swine plague bacteria, March 18. Animal dies 40 hours after inoculation. ; Inguinal glands slightly swollen and hyperemic. In abdominal cavity péritoneum pale pink, all minute vessels injected. Shreds of a viscid grayish exudate attached to abdominal walls, contiguous coils of intestines, and stomach. Considerable opaque reddish serum present. Vessels of diaphragm injected; some ecchymoses observed. The shreddy exudate also present. The mesentery edematous, especially where 30 attached to intestines. The walls of a portion of the lower small intestine very much swollen, serosa dark red. On the mucosa which is congested a yellowish, pasty exudate loosely rests, occupying the side to which mesentery is attached. This exudate is made up of leucocytes imbedded in strands of fibrin. Peyer’s patches along this region and down to ileo-cwcal valve are deeply congested and swollen so as to appear boat-shaped. (The bacteria had evidently traveled along mesentery and invaded the walls of the small intestine. ) Large intestine distended with dry feces. Mucosa of cecum and colon more or less congested, the congestion limited mainly to summits of folds. The lymphatic patch near valve very hyperemic and swollen. In each pleural sac about 50 cubic centimetres of reddish serum. A thin membra- nous exudate covering the dependent half of both lungs easily scraped away as a pale yellowish pulpy mass. The remainder of pleura opaque, a barely visible exu- date covering it. The lungs are hyperemic, the free border of the ventral and ce- phalic lobes collapsed. Bronchial glands swollen and hyperemic. Pericardium thickened, clouded ; vessels injected. A barely visible exudate on it. Vessels of heart surface very much distended. Petechie on left auricle and under endocardium of left ventricle near semi-lunar valves. Right heart distended with a dark, soft coagulum. In the peritoneal exudate, which consists chiefly of fibrin and a few leucocytes, immense numbers of the injected bacteria are present, showing after staining the polar arrangement of protoplasm very distinctly. The pleural exudate composed of the same elements. In some leucocytes up to twenty bacteria. In the spleen and blood from the heart large numbers of swine-plague bacteria. Agar cultures from the spleen, pleural, and peritoneal cavities contain only the injected bacteria. A bouillon culture from the spleen likewise pure. INVESTIGATIONS OF 1889-'90. The problem of swine diseases as it stood after the completion of these investigations up to 1889 may be stated briefly as follows: Since 1885 a well-characterized bacillus has been encountered as the cause of an infectious disease termed hog cholera, which is chiefly localized in the large intestine. Since 1886 our attention has been directed to lung disease in swine with which a bacterium is associated, which, when inoculated into swine, proves to be very virulentand may give rise to pneumonia when the bacteria are injected into the lungs. This is sufficient to demonstrate the existence of a disease differing from hog cholera, which has been called swine plague because an identical dis- ease of swine in Germany, first described in 1885, was called Scehweine- seuche. This lung disease was shown to becommunicable. (LV.) * In many of the outbreaks examined the changes found in the intes- tines could not be distinguished from hog cholera (except perhaps in IV). In some hog-cholera bacilli were actually detected, in others (1, V1) they could not be found. One of the problems, therefore, still before us, and a very important one, was to determine whether all out- breaks of swine plague in which intestinal lesions closely resembling those of hog cholera are present are mixed outbreaks of swine plague and hog cholera, or are simply swine plague. Much light has been thrown upon this subject by the investigations of three outbreaks given in detail in the following pages. The firstis a mixed outbreak in which, however, the lung lesions are so very well marked and the swine-plague bacteria associated with these lesions so virulent that there can be little doubt that the hog cholera disease was really secondary to the swine plague. The second outbreak is simple, uncomplicated swine plague. Inthe third outbreak very virulent swine- plague bacteria, and, in one case, very attenuated hog-cholera bacilli were found. WADE An outbreak of swine disease appeared among the pigs belonging to an abattoir adjoining the Experiment Station about the first week in October, 1889. ‘The disease came to our notice a week after the first * These numerals refer to the different outbreaks as numbered in this report. 31 32 animals died, and in‘attempting to trace the causes which led to it we obtained the following information : The pigs were purchased in the markets of Washington City the lat- ter part of September. They were thirty-five in number, in two, possi- bly three, lots. One lot came in two crates. It could not be deter- mined whether it was made up of pigs from one or two sources. They began to die, as stated, about a week after their arrival. We examined in all thirteen animals, the first on October 12, the last on October 28. A few days later the last of these thirty-five pigs succumbed to the dis- ease. It lasted, therefore, about 1 month. A few large swine which were on the place when these animals arrived did not take the infection. In the following pages a detailed statement of the pathological and the bacteriological examination is given. Those who are not specially interested in these notes will find a summary of the ascertained facts following them. No.1. October 12. Male pig, weighing about 25 pounds, died last night. On inner aspect of right thigh an area, about one-half inch in diameter, of extravasation, ex- tending down into true skin. No ulcersin the mouth. Spleen not enlarged. Contents of stomach slight in amount, consisting chiefly of sand and a turbid liquid; walls contracted, throwing mucosa into large folds. The greater part of mucosa intensely congested. In the fundus a large ulcer 14 inches across, covered by a slough one-quarter inch thick. The subjacent wall nearly one-half inch thick, on ~ section deeply reddened throughout, due to a sanguinolent, edematous infiltration of the wall. Adjacent to this a smaller inflammatory thickening covered with a thin pultaceous slough. The mucosa of duodenum uniformly and deeply pigmented. In the ileum the mucosa is swollen, Peyer’s patches reddened. Mucosa of cecum of a bluish-gray color, dotted with a small number of ulcers not much larger than pins’ heads, covered with yellowish sloughs. Similar follicular ulcers on Peyer’s patch near valve. Upper colon contains much earth, adhering rather closely to mucosa. The latter quite deeply pigmented, the pigmentation intensified in lower colon. In upper colon a small number of flattish yellowish-white sloughs from one-sixteenth to one-eighth inch in diameter. In thorax, the pleura covering the diaphragm and ribs is overlaid by a pale pinkish membranous exudate, easily rubbed off and especially abundant on the right side. The various lobes of both lungs firmly glued together by exudate. The ventral lobes, the major portion of cephalic lobes, and a small portion of the principal lobes adjacent to the ventrals are hepatized. The hepatized areas are covered by false membranes varying in thickness and easily peeled off. Through the hepatized lobes are disseminated necrotic masses of a greenish color varying in size from mere specks to peas. They contain large numbers of swine-plague bacteria, which show a polar stain very clearly. The tissue around the terminal portion of both bronchi in the principal lobes is hepatized and contains necrotic foci. Lung worms abundant in the left bronchus. Both bronchi contain small quantities of reddish foam. Peri- cardium thickened, opaque; vessels injected; the ventral surface is covered by a membranous exudate and it is adherent to the heart surface by means of a similar exudate. Cover-glass preparations from the pleural and pericardial exudate, from various regions of hepatized lung tissue, contain large numbers of swine-plague bac- teria. A rabbit was inoculated October 12, by placing a bit of lung tissue under the skin of abdomen. Dead next morning. Slight ecchymosis in the subcutis at the point of inoculation. The blood and spleen contain immense numbers of swine-plague 33 bacteria, showing well the polararrangement of the protoplasm when stained. Cul- tures confirmatory, agar and bouillon being used chiefly. A rabbit inoculated at the same time and in the same way with a bit of spleen tissue. Rabbit dead next morning. Swine-plague bacteria fewer than in preceding case. Anagar culture from the blood contains only these germs. From the spleen two agar, one bouillon, and one gelatine tube culture prepared. On the second day (Sun- day intervening) a moderate number of isolated colonies on the agar surfaces; the condensation water turbid with flaky deposits. In the bonillon tube are a large number of minute suspended flakes, the liquid itself not clouded. In these cultures only swine-plague bacteria. The gelatine tube remained sterile. From the pleural exudate an agar and a bouillon tube were inoculated at the autopsy. On the second day a number of colonies similar to those on the spleen agar culture were found to be made up of swine-plague bacteria. The bouillon culture faintly and uniformly clouded. Only swine-plague germs present. From the epicar- dial exudate two similar cultures were prepared with the same result, with the ex- ception that in the bouillon culture large cocci were also present. With a bit of lung tissue taken from more recently diseased regions two gelatine rolls and two agar plates were made. In the second gelatine roll about 100 minute colonies present after 3 or 4 days. These were examined and bouillon tubes inocu- lated from four different colonies at different times. In ali the swine-plague germs only appeared. The first agar plate developed a very large number of colonies, the second only six or Seven, made up only of swine-plague germs, No. 2. Female; died last night ; weighs about 45 pounds. Lymphatics in the groin barely enlarged, pale. Spleen quite large, softened, dark red in color. Digestive tract: Stomach partly filled with chewed leaves, and straw adhering slightly to mucosa. Fundus faintly reddened. The pyloric portion bile-stained. Duodenum similarly stained. An ascaris in the bile duct, projecting 14 inches out into duodenum. Arborescent injection of mucosa of the latter. Considerable quan- tity of turbid liquid in large bowels. Mucosa not pigmented. Peyer’s patch at base of valve thickened and pigmented. Ulcers moderately abundant in excum and upper colon. They appear as little cup-shaped depressions, one-sixteenth to one- eighth inch in diameter,lined with a pale yellowish necrotic layer, the center in some filled with a black slough and the margin elevated. Mesenteric, mesocolic glands, and those of lesser omentum, slightly swollen; cortical layer congested. Interlobu- lar markings of liver prominent, broadened. The section appears mottled, some lob- ules being much more congested than others. The empty gall-bladder contains a partly disintegrated ascaris, which extends through bile duct into duodenum. Thorax: The costal pleura of both sides highly injected and covered with a thin, whitish membranous exudate, gluing the lungs to the chest wall. Of the lungs all but a small strip along the dorsal border of the principal lobes is solid, three or four times the size of the normai lung when collapsed. The various lobes are glued to each other, forming a single mass, in which the individual lobes are not recognizable, and which is in turn attached to the chest wall, the diaphragm, and the pericardium by pleuritic exudate. This is most abundant, and forms membranes on the most de- pendent portions of the lungs, easily pulled away from the subjacent structures, The various adhesions torn without difficulty. The disease seems farthest advanced in the cephalic and ventral lobes, in which are imbedded a large number of closely set masses of dead tissue, from one-sixteenth to one-half inch in diameter. These are firm, yellowish masses, sharply defined in outline, and imbedded in dark red hepatized tissue, which is mottled with paler specks, representing the ultimate lobules distended with cell masses. The trachea and bronchi contain whitish foam, mixed with large quantities of thick, purulent secretion. In the bronchi of the principal lobes are many lung worms. The bronchial glands are hyperemic and cdematous, and contain a small number of necrotic foci. 1614 3 34 In the spleen a few minute oval bacteria detected. With a platinum needle the surface of an agar tube and a bouillon tube inoculated. On following day the former showed a considerable number of round, grayish colonies, 1} to 3 millimetres (one-sixteenth to one-eighth inch) in diameter; condensation water clouded. In this tube only swine-plague germs detected. The bouillon culture contains a considerable number of minute granules, representing clumps of swine-plague bacteria. An agar culture from the liver grew like the spleen culture and contained only swine- plague germs. At the autopsy an agar and a bouillon tube inoculated from the right pleura. In the former only the condensation water became turbid and contains swine-plague germs exclusively. The bouillon tube remains sterile; similarly a bouillon tube from pericardial exudate remains sterile. (It is highly probable that the flocculent growth of the swine-plague gernis in bouillon and the sterility of these tubes was occasioned by an unsuitable condition of the bouillon, ) From a bit of lung tissue, the pleural surface of which had been thoroughly scorched, gelatine roll cultures were prepared. After a number of days the first roll showed a large number of colonies as mere points, the second roll about 100 colonies, somewhat larger, From both tubes bouillon was inoculated from individual colonies, These contained after development only swine-plague bacteria. At the same time the scorched lung tissue was pricked with platinum needle and an agar tube inoculated. On the surface a considerable number of similar colonies appeared on the following day. Some of these examined were swine-plague germs, In the condensation water a few chains of a short, motionless rod appeared among the great bulk of swine-plague germs. At the same time a rabbit was inoculated from the lung tissue. It was dead next morning. Enormous numbers of polar stained swine-plague germs found in stained preparation of spleen pulp. An agar culture confirms the microscopic examination. No. 3. Died last night. Female; weighs about 25 pounds; in very poor condition. Spleen considerably engorged ; contains a small number of bacteria; nature to be determined by cultivation. Digestive tract: One ulcer on the gums of lower jaw. Stomach contents like those of No. 2. In the fundus an area of mucosa, about 4 inches in diameter, is nearly black from extravasation, and thickened. A zone several inches wide outside of this is deeply reddened. The mucosa of duodenum and ileum more or less discolored the vessels, showing arborescent injection. In the cecum, the mucosa is of a bluish- gray color, and dotted with a dozen sloughs, one-eighth inch diameter, of a yellow color; the tissue at the margin of the slough thickened, elevated, The Peyer’s patch near valve deeply congested and sprinkled with enlarged grayish follicles. Mucosa of colon more oF Jess discolored and hyperemic in patches; only three small ulcers found. The liver appears normal, the bile in bladder very thick, flaky, Punctiform ecchymoses on surface of kidneys. In the lungs the major portion of both ventral lobes is solidified, the tips being emphysematous. The hepatized portions are bright red in color, with faint yellow- ish mottling. Bacteriological examination: Cover-glass preparations of the hepatized lung tissue show no bacteria. From a bit of tissue two gelatine roll cultures prepared anda rabbit inoculated. Roll A subsequently contained a large number of apparently iden- tical colonies. Roll B, about fifty of the same colonies and one chromogene. Care- ' ful examination of these revealed hog-cholera bacilli. The inoculated rabbit died within 36 hours. At the place of inoculation the bit of lung tissue was surrounded by a small area of purulent infiltration and dilated blood-vessels. In the blood and spleen a very large number of swine-plague bacteria. A bouillon culture from the blood faintly clouded on the following day, and holding in suspension barely visible granules made up of clumps of swine-plague bacteria. No motile bacteria detected. The spleen of the pig contained 9 few bacteria, character not determinable. Witha 35 bit of pulp a gelatine roll A and agar plate B prepared, also a bouillon culture. The latter was uniformly clouded on the following day; a few gas bubbles on the surface. Only motile hog-cholera bacteria present. ‘The presence of hog-cholera bacilli in the spleen was furthermore demonstrated by the roll and plate culture, The agar plate grew, of course, most rapidly, being in the thermostat. On the second day a consid- erable number of colonies appeared, apparently the same. Examination of some showed only hog-cholera bacilli. A bouillon tube inoculated from one of them was clouded on the following day with motile hog-cholera bacilli. One-fifth cubic centimetre of the original bouillon culture was injected subcuta- neously into a rabbit. On the fourth day temperature 106.19 F. Found dead on the seventh day with the usual lesions of hog cholera, such as engorged spleen, necrotic foci in the liver, reddened Peyer’s patches, hemorrhagic points on the lower colon and rectum. Spleen and liver contain hog-cholera bacilli in moderate numbers. From spleen an agar and a bouillon culture prepared by piercing spleen with a fine platinum needle and inoculating culture media therewith. In both only hog-cholera bacilli appeared. ‘The original spleen culture contained no swine-plague germs, otherwise the rabbit would have succumbed within 1 or 2 days. In the gelatine roli appeared after a few days a very large number of the same colonies, evidently all hog cholera. No. 4. October 14. Small male pig, weighing about 30 pounds ; died last night. Skin of abdomen slightly reddened. Subcutaneous inguinal glands enlarged, edematous, mottled red and pale. Mouth free from ulcers. Contents of stomach stained with bile. Mucosa of fundus over an area 4 inches square deeply congested, swollen, Slight injection of minute vessels in duodenum; remainder of small intestine normal. Large intestine con- tains a turbid liquid and a substance resembling coal ashes. ‘The mucosa of cecum studded with superficial, yellowish sloughs, about the size of pins’ heads or a little larger. In the colon, besides these small yellowish sloughs there are three or four large areas over which the mucous membrane is entirely necrosed superficially. These areas are about 6 inches long. The minute sloughs limited chiefly to the upper half of the colon. Liver rather firm in texture, the acini projecting slightly above interlobular tissue on the surface. Glands near the portal fissure deeply congested throughout. Dilatation of pelvis of kidneys encroaching on medullary portion to a large extent. Both ureters very much distended ; walls from one-half to three-quarters inch thick. Lungs collapse when removed from thorax; no pleuritis. In all the lobes there are masses of collapsed and hepatized tissue varying in diameter from one-half to several inches. They are situated chiefly near the roots of the lobes. The small median lobe in part hepatized, bright red with yellowish mottling. In the terminal bronchi are plugs of lung worms imbedded in thick muco-pus. The tissue around the plugs in the left principal lobe hepatized. Bacteriological examination : With bits of diseased lung tissue two gelatine rolls were prepared and a rabbit inoculated. The rolls both contained on the second day an immense number of colonies of micrococci, evidently a contamination of the gela- tine. The inoculated rabbit died in 4 days with enlarged spleen and patches of necrosis in the liver in the form of a net work. An agar culture from the spleen and a bouillon culture from heart’s blood both subsequently contained only hog-cholera bacilli. No swine-plague germs detected, although the rather premature death of the rabbit led me to suspect their presence. Some weeks later a rabbit was inocu- lated subcutaneously in the ear with a platinum loop of the blood culture of the preceding rabbit. This rabbit died in 5 days with hog-cholera lesions. With a bit of spleen pulp of the pig a gelatine rol] A and an agar plate B were prepared; also a bouillon tube inoculated with platinum needle after pricking the spleen. This developed into a pure culture of hog-cholera bacilli. In the gelatine roll appeared numerous colonies of hog-cholera bacilli. The agar plate was partially overgrown ; the few isolated colonies were made up of hog-cholera bacilli, 36 From the liver a gelatine roll, an agar and a bouillon tube inoculated, each with minute particles of tissue. In the roll numerous colonies appeared, evidently all hog cholera. The two tube cultures likewise contained only hog-cholera bacilli. No. 5. October 15. Small male pig, weighing about 25 pounds, died last night. Skin about urinary meaius reddened. Subcutaneous inguinal glands enlarged, firm, juicy, faintly mottled with red. Stomach contracted. Contents same as in preceding cases. Mucosa in large folds, summits of which somewhat reddened. Slight discoloration of mucosa of lower ileum. Contents of large intestine firm, in form of lumps. In the cecum about ten ulcers, from one-eighth to one-half inch in diameter, the Jargest button-shapped, flattish, a firm, yellowish, necrotic base extending into subjacent muscular coat. Complete necrosis of Peyer’s patch at valve. In the colon a small number of large and small button ulcers. The solitary follicles projecting as large as split peas. When squeezed a white soft mass exudes from a central depression. Liver rather firm in texture. Gall bladder contains semi-liquid, flaky bile. Spleen slightly enlarged. Kidneys on section very pale. Both lungs edematous. Hepatization involves the free tip of both small cephalic lobes of the right lung, the major portion of the ventral lobe of the left lung. In both principal lobes are a moderate number of small hepatized foci. In both bronchi a large quantity of very viscid muco-pus, which extends down into the branches of the principal lobes. These latter and the terminal portion of the principal bronchi contain plugs of limg worms. Bronchial glands enlarged, firm, pale. Bacteriological examination: In cover-glass preparations from the spleen a very tew bacteria resembling somewhat hog-cholera bacilli seen, An agar culture inoculated with platinum wire remained sterile. * On the following day spleen taken from re- frigerator and a second agar tube inoculated with particle of pulp. In this tube a colony of greenish fluorescent bacilli appeared. From hepatized lung tissue two gelatine rolls were prepared. The first one was spoiled by a few liquefying colonies; the remaining small colonies were inaccessible. The second roll remained sterile. A rabbit inoculated subcutaneously with a particle of lung tissue died in 24 hours. At the place of inoculation considerable purulent thickening of skin with eechymosis of the subeutis. Numerous very small coccidia cysts in liver. Spleen enlarged, congested. (Bacteriological notes of this rabbit mislaid-) No.6. October 15. Small female in very poor condition; died last night; more or less decomposition. Ventral aspect of body reddened. Subcutaneous inguinal glands enlarged, firm, and very hyperemic. Stomach much contracted, empty. Mucosa of fundus beset with punctiform hem- orrhages. Small intestine not marked by changes; one ulcer in lower ileum, Con- tents of cecum and colon of a somewhat pasty consistency mixed with coarse sand. In the cecum about six old, flattish ulcers, from one-fourth to one-half inch in diam- eter, also a patch of easily removable, membranous exudate several inches square: In the colon near the valve several ulcers and a similar patch of exudate. In the lungs the hepatization, though extensive, is more or less scattered in foci as follows: A few hepatized foci in left cephalic, one large hepatized mass in ventral, and four wedge-shaped masses in left principal lobe. In the right lung, fully two-thirds of the median and the whole of the ventral lobe solidified. The latter lightly glued to the neighboring lobes. Disseminated through it are very many necrotic foci about one- eighth inch in diameter. In the right principal lobe several hepatized masses. In both bronchi a large number of adult lung worms. Pericardium thickened ; vessels injected. Spleen not enlarged or congested. Bacteriological examination: Spleen found more or less decomposed. No ; germs in cover-glass preparation. In an agar culture therefrom numerous isolated and conflu- ent hog cholera colonies appeared on following day. A rabbit inoculated subcutaneously with a bit of lung tissue (the particular region 37 not indicated in the notes) was found dead on the eighth day. Extending from the point of inoculation over the entire abdomen and portion of thorax the subeutis is infiltrated with a yellowish, pasty mass of pus, stained with blood. The superficial layer of muscles discolored, ecchymotic. Spleen slightly enlarged. No peritonitis. Cultures from the spleen remained sterile. An agar plate from the subcutaneous exu- date spoiled by condensation water. An agar tube from the same source remained sterile. No.7. October 15. Small male pig, of about 35 pounds, died yesterday afternoon late and put in refrigerator until next morning, Animal in fairly good condition. The lesions in this case were briefly as follows: Digestive tract: Fundus of stomach faintly reddened. Small intestine not affected. Contents of large intestine liquid, of black color, holding much earth in suspension. One ulcer on the thickened Peyer’s patch near the valve. Follicles swollen. Noother changes. Lungs: General pleuritis indicated on the most dependent portions of the left lung by a thin, membranous exudate, elsewhere by roughening. The various lobes lightly glued together. Hepatization limited to the tip of the left ventral and a small area in the left principal lobe, containing numerous necrotic foci. In the right principal’ lobe two wedge-shaped, hepatized masses, in which are many minute oval germs, re- sembling swine plague. Generalized bronchitis indicated by much curdy muco-pus in the bronchi and branches. No lung worms detected. In the liver, the center of many lobules in all the lobes of a brick-red color, caused by fatty degeneration of this portion of the lobule. Bile very thick, dark-colored. Spleen very much enlarged, softened, dark colored, Bacteriological examination: From this animal only the spleen and the pleural exudate received any attention. An agar tube inoculated from the spleen simply with a platinum wire was sterile on the following day, although bacteria had been detected in the spleen pulp in cover-glass preparations. A second tube inoculated with a particle of pulp from the spleen, kept meanwhile in the refrigerator, developed a large number of isolated and confluent colonies. So far as could be determined these were all swine-plague bacteria. No motile bacteria present. An agar culture made at the autopsy from the pleural exudate proved to be a pure culture of swine-plague bacteria, No. 8. October 17. Male pig, weighing about 35 pounds, died last night. Sub- cutaneous inguinal glands enlarged, on section dotted with minute petechi:e. Stomach normal. Duodenum bile-stained. In lower ileum much liquid, containing fine earth and sand. In cecum minute vessels of mucosa injected. Peyer’s patch at valve somewhat swollen and discolored. In the upper colon several small patches of thin exudate, about one-fourth inch in diameter ; the subjacent epithelium appeared necrosed, In both kidneys infarcts of a yellowish, homogeneous appearance, sur- rounded by a hyperemic zone, and visible from the surface of kidney, two in the left and twelve in the right. Spleen somewhat enlarged, firm. Liver very pale, pulp rather soft. On the left lobe several paler spots, not elevated, about one-fourth inch in diameter. Bile thick, flaky. Lungs everywhere adherent to surrounding structures by means of a membranous exudate, grayish, elastic, coming away in patches and shreds when pulled. This membrane especially thick between lungs and diaphragm. The various lobes matted together and adherent to pericardium. Lungs do not collapse. Left ventral and cephalic lobes completely hepatized. Throughout both are dis- seminated a large number of greenish-white, homogeneous, firm masses from one- fourth to one-half inch in diameter. Almost entire right lung hepatized. In the cephalic lobe, ventral lobe, and cephatic portion of principal lobe the necrotic masses are very numerous, one near tip of ventral lobe quite large. The hepatization of the principal lobe is of the dark-red variety. 38 Large quantities of lung worms in left bronchus and branches contained in the caudal third of principal lobe. Right bronchus not opened. Pericardium thickened, opaque. Heart surface covered with a thin, transparent pseudo-membrane. Left auricle hemorrhagic. A clot distending the right heart and forming of it a complete cast. Center of clot pale. Bacteriological examination: From spleen two agar cultures made. One remains sterile. In the other on second day a faint growth starting from condensation water upwards, The latter contains clumps of swine-plague bacteria and large bacilli with terminal spore. Several gas bubbles in agar. From the pleural exudate of right lung an agar and a bouillon culture prepared at autopsy. On following day a large number of punctiform colonies on agar surface. Minute flakes in condensation water. In bouillon minute granules, representing clumps of minute oval cocci. In both tubes only swine-plague bacteria. From the more recently hepatized regions of lungs which contain large numbers of swine-plague bacteria and some large bacilli, two gelatine rolls and two agar plates prepared. In the gelatine roll A two forms of colonies appeared, one with disk homogeneous, the other with a distinct peripheral zone. In roll B only one kind appeared. A number of bouillon tubes were inoculated from colonies in roll B which turned out to be streptococci. From roll A bits of gelatine were removed to bouillon with warmed platinum needle, some cultures remainéd sterile while others contained streptococci. On the agar plate A, large numbers of apparently identical colonies appeared. On plate B, a moderate number developed. Of these a few examined were made up of swine-plague bacteria. A large rabbit inoculated with a particle of lung tissue died within 20 hours. No internal changes, excepting a probably preéxisting fatty condition of the liver. Few swine-plague bacteria detected with the microscope. An agar and a bouillon culture from heart’s blood contained only swine-plague bacteria on second day. No. 9. October 18. Female pig; died last night; weighs about 30 pounds. Sub- cutaneous glands of groin enlarged, firm, cortex hyperemic. One small necrotic patch on mucous surface of lower lip. Stomach with fundus pale, pyloric region bile-stained, Around the cardiac expansion are about thirty yellowish-white, confluent, and isolated ulcers from one-eighth to one-fourth inch in diameter. They are raised above the level of the mucosa, flat on top. Projecting slough soft, friable; base of ulcer very firm, extending into muscular coat. Mucous membrane of duodenum bile stained ; arborescent injection of minute vessels. Mucosa of ileum more or less discolored and inflamed. Large intestine with walls very mueh infiltrated and mucosa extensively destroyed by necrotic changes. In the cecum, a large patch of ulceration having a peculiar gnawed appearance, surrounding islands of intact mucosa. On section the mucosa is found converted into a yellowish-white, firm mass. In the colon patches like these are interspersed with a large number of isolated cir- cular ulcers with blackish, depressed surface and a subjacent yellowish, firm, thick base extending into the muscular coat. Besides these, there are a considerable num- ber of ulcers with an elevated, soft, necrotic top, easily scraped away. In lower colon, large patches of destroyed mucosa. Spleen very large, friable, pulp very dark. Liver tissue apparently unaffected. Bile rather thick. Kidneys with parenchymatous degeneration of cortex. Lungs as whole much affected. In the right lung all but the dorsal third of the ventral lobe solid, enlarged, bright red, with large and small masses of a pale-greenish color disseminated through it. A portion of the cephalic lobe solid, in the same con- dition. One-half of the median lobe similarly diseased. The principal lobe glued to ventral lobe by a thin pseudo-membrane. About one-third along the ventral aspect solidified in masses from one-half to three-fourths inch in diameter, these masses ex- tending from diaphragmatic to convex surface of the lobe. The interlobular tissue 39 around these hepatized masses distended with serum. The various lobes of the left lung are in the same condition as the corresponding ones of the right lung. Pleuritis only over the hepatized regions in the form of a delicate network. The trachea and bronchi contain much frothy muco-pus. In the left terminal bronchus, surrounded by hepatized tissue, are masses of lung worms completely ocelud- ing it. Bronghia! glands large, pale, containing a variable number of small necrotic foci. Bacteriological examination: From the right pleural sac a bouillon and an agar tube were inoculated with platinum loop. In both only swine-plague bacteria sub- sequently appeared. From a more recently hepatized region of the lungs two agar plates were prepared with a loop of the serum, in which microscopic examination had shown an immense number of swine-plague bacteria. Plate A contained, after several days, a small num- ber of miscellaneous colonies and a very large number of barely visible colonies, which proved to be made up of swine-plague bacteria, On Plate B no development. From the more advanced disease two gelatine rolls were prepared from a particle of necrotic tissue. Roll A liquefied. Roll B, after a week’s time, contained about twenty-five small colonies of the same character, resembling hog cholera, and one large colony. The former transferred to agar, and bouillon tubes proved to be not hog cholera bunt streptococci. A rabbit inoculated with a bit of diseased lung tissue died within 20 hours. Organs not changed. At point of inoculation considerable purulent infiltration. In blood and spleen a very large number of swine-plague bacteria, showing in stained prepara- tions the polar stain very well. Cultures in bouillon and on agar confirmatory. From spleen a particle of pulp used to prepare one bouillon culture and an agar plate. In the bouillon the motile hog-cholera bacilli appeared among clumps of swine-plague germs. On the plate after several days a moderate number of colonies of one size and a very large number of colonies of a very small size appeared. Some of the former examined are hog-cholera bacilli, the latter swine-plague bacteria. From particles of liver tissue the same cultures were made, and the same mixture of hog-cholera and swine-plague bacteria found. Sections from more recent pneumonic infiltration prepared from material hardened in aleohol show a considerable amount of fibrin in the alveoli, in whose meshes are a few leucocytes and very many of the minute swine-plague bacteria. The peribron- chial and interlobular lymph spaces are distended with fibrin and cells and contain very many swine-plague bacteria. Sections prepared from tissue in which the disease is much more advanced show a complete occlusion of the alveoli and small air tubes with dense cellular masses in which swine-plague bacteria are more or less abundant. The tissue surrounding such foci contains in the alveoli a moderate number of round cells, largely intermixed with fatty cells. Bacteria absent. " No. 10. October 19. Small male pig in poor condition, weighing 21 pounds. Died last night. Subcutaneous inguinal glands very large. On section punctiform hem-_ orrhages and irregular masses of apparently necrosed tissue observed. In the stomach a considerable number of single and confluent ulcers with project- ing, yellowish, friable slough, resting ona firm, indurated, whitish base. The mucosa of small intestine shows extensive arborescent injection of minute vessels. Contents of large intestine, a chocolate-colored liquid containing much sand. The lesions of the mucous membrane are about as extensive as in case 9, The larger patches show more diptheritic deposit than in preceding case. Spleen very large, blackish, friable. Cystic degeneration of both kidneys. Lungs extensively diseased. Nearly the whole of the left lung excepting the caudal half of the principal lobe hepatized, and covered with a thick membranous exudate. This is readily peeled off in shreds and larger patches, especially dense on the ventral and cephalic lobe and adjacent pericardium. Lobes adherent to one another; adhe- 40 sions easily loosened. The ventral Jobe is a mottled bright red, The small air tubes occluded with semi-solid plugs, easily squeezed out. This condition not observed in the other lobes, excepting in the principal, in which the terminal bronchus and ~ branches are occluded with plugs of lung worms and muco-pus. Tn the right lung, the ventral lobe in the same condition as corresponding lobe of left side, containing in addition numerous necrotic foci. The cephalic fifth of prin- cipal lobe hepatized; the hepatization of a bright red color, with faint regular yel- lowish mottling. Cephalic half of the small median lobe in the same condition. The bronchi in the tip of principal lobe occluded with masses of lung worms and in part hepatized. In trachea and bronchi much muco-pus. Bacteriological examination: In preparations from the spleen bacteria not detected. An inclined agar tube inoculated with piatinum needle contained in a few days a large number of minute apparently identical colonies. So far as could be determined — no hog-cholera bacteria present. x x x< Dies.s.[ssee04s Negative (hog- cholera bac- teria?) 17 x x x x x x Xx Dies Negative. a = —=——= SZ = — — = — — B2BS Iloaaonin coosicd MCAS ase GocanGesd SS aeeenn arecrset: Exposed .. x 384 | Exposed.. x x x x x x x Bt) | GS Be eae x x *< x x x Dies Argust 9 of swine plague. BaD lloodosecccHod pecds God bostecud lsSdneas| Hensosea BAA assa66| aeopecal baorsras Exposed Aug. 9. Rey | oondicaocod |Zeacnpe0 bedccnes Sectoeod ssedeaed sccoaencased peseuone Bortencer Do. The result of this exposure was the death of No. 385 of swine plague. In the lungs were disseminated numerous hepatized foci undergoing necrosis. There was considerable plastic pleuritis matting the lobes to- gether. In the digestive tract extensive hyperemia bordering on hemorrhage. Swine-plague bacteria were obtained from the lungs, pleural exudate, heart’s blood, and large intestine. Cultures were also made from the spleen, liver, mesenteric glands, and kidneys, to make sure that if hog-cholera bacteria were present they should not be over- looked, but none could be found. A clearer demonstration of the disease- producing power of swine-plague bacteria could not well be obtained. The importance of this case warrants the publication of the notes in detail: No. 385. Black Essex grade, aged 3 months, placed in pen containing Nos. 13 to 17, inclusive, on July 29. Found dead August 9, rather unexpectedly, after a sickness lasting but 2 days, and manifested by dullness and refusal to eat. Examined a few hours after death; kept on ice in the meantime. As the skin is reflected, the cut subcutaneous blood vessels discharge drops of dark blood. In ab- dominal cavity nothing abnormal. Pericardium thickened, opaque, vessels injected, Left half of heart firmly contracted. Eecchymoses on the right auricle. Right side contains a pale clot imbedded in a dark coagulum. 70 Respiratory tract: Mucosa of larynx and epiglottis congested. Mucosa of trachea covered with a very thin layer of translucent, very viscid mucus. Bronchial glands enlarged, pinkish on section. Costal pleura of the right side discolored, thickened, overlaid by a soft grayish exudate ; its blood-vessels injected. Diaphragm similarly affected. The various lobes of the lungs lightly glued to one another and to the peri- cardium. Considerable pleuritic exudate on the right ventral and along the edges of both principal lobes. Lungs in general hyperemic. Left cephalic lobe emphysema- tous; left ventral shows hemorrhagie spots near its tip and contains two firm nod- ules, appearing as yellowish spots under pleura. Left principal lobe contains four of these spots corresponding to firm nodules in the parenchyma. Besides these, a wedge-shaped, very firm, hepatized mass extends inward from the edge and almost through the depth of the parenchyma. These various masses appear yellowish, homo- geneous, imbedded in hyperemic, air-containing tissue. They vary from one-eighth to five-sixteenths inch in diameter, nearly all of them situated near the surface. The largest ones are covered by roughened, thickened pleura, thrown into wrinkles; these are in part yellowish, in part bright red and pink in color. The three lobes of the right lung contain these necrotic masses. There are several in the right cephalic, about six in the ventral, and over a dozen in the principal lobe, the largest being one-half inch in diameter. Digestive tract: Several small superficial sloughs on dorsum of tongue, near tip. Stomach contains a considerable quantity of food. Fundus deeply reddened over an area 5 inches in diameter. Duodenum with its mucosa bluish-gray, pigmented. Pey- er’s patch showing as an aggregation of small, depressed pigment spots. Arbores- cent injection of jejunum merging into a general hyperemia lower down. About 18 inches above valve a patch of mucosa 2 inches long, intensely reddened. Extensive pigmentation of mucosa of cecum. Mucous glands at the valve dis- tended with plugs. About 12 inches below the valve the mucosa is intensely red- dened, merging on hemorrhage. acisseine oa se biemsiccee ee 91, 145 Lofiler, investigations of swine plapue by <2---- --- os sea ams =e aloes oe 125 Lung disease in swine plague .......... 3 Saiale wlelclwioferne ee amin = seisieeicisicele eee eee 98 Lungs Ol swine descrip hioneOta- cess ee yes eee eee = Sere eee ee eee 17 injection of swine-plague bacteria into-...-....----- 21, 29, 45, 71, 113 Lung worms associated with swine plague ..-.... 2.22... 220 ene penne ene nne 104, 134 in‘outbreaks NON-MOtile secant see ee Se ee aoe eee eee 86 objects which may carry .......-.----- Sgbeeeceee:s 145 pathogeniciactionyOles-s see aceociies-creceser eee aieces 96. producing phenol and indol in cultures.........-..-. 89 readily destroyed by various agents. .......-...--..- 90 eansed by directnniections.-secc ene ciene = lata eee elaine 69 conditions which may favor and oppose...-...--...---.------ 133 Mi Germanys ceeee eae eee eee ea ae ecm inee one eemieeae seer ete 125 investigationsibysblings wh. Smee seseeeee ices mee eee ieaecae 118 Bleisch:and Piedeler mss. s--e see cree selene 129 Burrill ease, oe se corse cis eekeec een ose eee 124 OMICS Jam csc neces coeslsoaa ieee enueece mics 123 IU Gag seeBee socdoCHenes choo eudeds sdacacce 125 Peters). occ esc siccrse ec sche een een oceeere 131 Schultz, 5-52 Jose sce. eae sees ose eeeeciese 126 Welchvand Clements te-p--5 225 - eee eens 122 in) DistrictrosColumbiascceaneeeeeeeseeee eee 23,31 Germany 2252 -sctesiencee see eciace: os oeeeeeer 125 THin 018 :..0.52,25 = coe 2s oso sleet oe laceeneiene 20,124 TOWidine cctsarcinye occa cio ee eee as ecleeeeeen 23, 28 Maryland is 22/2 2.0.0 cecliccme saree cniesa meeps Pople a Massachusetts. MMe. -c2-scieine Secon cemee 123 MisSOUTLe 2 ..2cicche> obese s couse cemioceesisces 82 N@WJeTse Vice cicccte sosositeeeee meee oeiaceaee 57 its relation to hoo. cholerae eceeee eee eee eee ose eee 106, 138 modified Dy vaccinations. se. ac. wocee eae eee eee tee ieee 94 Outbreaksiofe. =.ss- case sae soe ee oee ae 19, 20, 23, 27, 28, 31, 47, 57, 82, 84 OOVGINWON Clic coos caeoass cspeco ps0 Oe0G00 codsoy Sad5 bad que Ste 133, 145 preventiveimoculation for. -2.\2 a. cee as mesos) eo eseeeee 148 treatment Oise. 2 css5-5 acccemerace senses serecioc ear emeriecer 146 with reference to humandisease @-o. sac eee ee eee eens 108 Table showing difference between hog-cholera and swine-plague bacteria ... 92, 105 distribution of hog cholera and swine plague........-..----- 140 Temperature at which swine-plague bacteria multiply .........--..--..---- 89 ireatment ofis wine plague sscess ssa os cae see ceee cles letsnce ese eer eee seis 146 Varieties of hoo-cholera bacilli 222225222 sss ae eal ce ice ecisaceyeceoe se eee see 1338 SWING-Pl ag VOM sO PORN ese ee eel te eee ee eae eee eee 93, 136 Virulencerof bacteria,impocvance Ole sesee ee eeees eee teresa ee ae eaeeeeee oe 117 Swine-plague bacteriaye rea cin oe sais elecee ce alninte einen rereilrers 135, 144 Water, destruction of swine-plague bacteria in-..---.-.---..-.---.----. 6... 92 Welch, W.H., and Clement, A. W., report on swine plague .........-....... 122 White washas aidisinfectant--- 2co:..-seisisanare- siete ne ca suneieiheeeeectetaete ences 146 LUO EON TOES 8 SES0 650605 BEGd DSS EES HONG obEOos deo SEDUEC nejslefseinisfeisie cere enieels 141 )