tion and often complete death of the mucous membrane of the large intestine, involving in the severest cases a similar destruction of the mucous membrane of the ileum. In the autopsy notes given by Schütz the alimentary canal is invariably intact or the slight changes due to general causes. The lesions are limited entirely to the thoracic organs, where the lungs are primarily affected by a "multiple mortifying pneumonia." Thence the disease may involve the pleura and the pericardium.

In hog-cholera, lung lesions are quite secondary and only rarely seen. In the severest hemorrhagic type of the disease we have almost always observed hemorrhagic foci scattered through the lung tissue, but these were no more numerous or more extensive than the extravasations found in most of the other viscera. It is quite easy to believe that such cases surviving the first severe attack may develop a pneumonia by the gradual extension and confluence of the separate foci. In all cases where the causation of such lesions is a matter of doubt bacteriological investigation must now decide.

Relation of infectious pneumonia to this disease.--It is of considerable importance to find out what relation this microbe of the German Schweineseuche bears to the one which we have recently found in pigs as the cause of infectious pneumonia. Morphologically they are evidently the same. So far as their growth in culture media and their biological properties have been observed there seem to be no grounds for regarding them as different species. As to their pathogenic properties we find some marked differences. The evidence which has been brought forward in the preceding pages that the microbe there described is the cause of a pneumonia in pigs, which is therefore, from an etiological standpoint, wholly different from hog-cholera, is not yet conclusive, and will require further investigations. Yet the facts there recorded are strongly in favor of the view that we are dealing with a hitherto unrecognized disease. The microbe was obtained from three outbreaks hundreds of miles apart. In the animals examined pneumonia was present. In the one outbreak hog-cholera was also present, as demonstrated by the lesions and the specific bacterium. The presence in the same herd of two diseases, and even in the same animal of two wholly different microbes which produce them, complicates matters very greatly. The disease described by Schütz as Schweinesueche is essentially a localized disease, involving the lungs only. There are no lesions of the intestinal tract. Is, then, this Schweineseuche the same as the pneumonia which we have found? Let us compare for a moment the microbes. Both destroy mice, the microbe of Schweineseuche more speedily and invariably. The same may be said of rabbits. Inoculation on the ear caused death in one to three days, according to Schütz. The same mode of inoculation produced death with the American form in nine days, and even subcutaneous inoculations do not prove fatal in less than three days.* Guinea-pigs are only in part susceptible to both microbes; pigeons to both when large quantities of virus are introduced into the system. Fowls are killed by the American form in large doses. Schütz does not report the use of large doses with these birds. Both produce extensive pathological changes at the point of inoculation in the susceptible animals.

*The microbe obtained from Iowa is more virulent than this, and resembles more closely the German form. These lines were written before this had been investigated.

When we come to their effect upon pigs after subcutaneous inoculation marked differences are manifested. Pigs inoculated by Schütz died from one to three days after inoculation. Besides producing rather severe local reaction, the bacteria had multiplied in all the internal organs and were easily demonstrable in cover-glass preparations. Those inoculated with the American form at the experimental station died in from one to two weeks. The quite constant pathological change consisted in acute contraction or cirrhosis of the liver, followed by jaundice. The bacteria had been meanwhile destroyed, for cultures from such cases remained sterile. Feeding either in cultures or in animal tissues failed to produce the disease. Schütz succeeded, however, in producing pneumonia from inhalation of cultures. Our experiment failed, perhaps, because the spraying was not continued long enough.

These differences, apparently very wide, may after all depend simply upon a difference in virulence; and it may be possible for us to obtain from other outbreaks a microbe which is as virulent as the one described by Schütz. There is every reason to believe that this mircobe loses its virulence very speedily in artificial cultures. This may have modified somewhat the results, since several weeks elapsed between the time the cultures were prepared from the affected animals and the time when the pigs could be inoculated therewith.

Schütz* and others are inclined to regard the microbe of Schweineseuche identical with the one which has been found to produce septicæmia in rabbits. In this connection it is of interest to mention briefly some experiments made with a microbe obtained from rabbits, which seems to be closely related to, if not identical with, the microbe of rabbit septicemia as described by European observers, and may perhaps be a modified form of the microbe found in pigs. This it resembles in form and mode of staining at the two extremities, but it is, as a rule, somewhat larger. It also differs in forming a more or less complete membrane at the surface of the culture liquid two or three days after inoculation. In its effect upon animals, that upon rabbits is especially characteristic. It destroys them within two days when injected hypodermically. There is a slight purulent infiltration at the seat of injection, varying in intensity with the duration of the disease. The bacteria are present in large numbers in all the internal organs, giving the disease the character of a true septicæmia. Fowls are insusceptible. Of seven pigeons inoculated, three died; of four guinea-pigs, one. Mice are less susceptible than rabbits, but more so than guinea-pigs.

We must regard this microbe as more virulent to rabbits and less so to other animals than the one found in pigs. As regards its effect upon the latter no extended experiments were made, excepting to note that doses of 1ce culture liquid produced no effect upon two animals. Perhaps future experiments may throw more light upon the relation of this microbe to the disease of swine, which we must consider, at least for the present, as a hitherto unrecognized infectious pneumonia.

* Loc. cit.

+Huppe: Ueber die Wildseuche u. ihre Bedeutung für die Hygiene. Berliner klinische Wochenschrift, 1886, No. 44.

For a detailed account, see the Quarterly Journal of Comp. Medicine and Surgery for January, 1887.

UNITED STATES NEAT-CATTLE QUARANTINE.

The Superintendents of the various neat-cattle quarantine stations report the names of the importers and the number and breed of each lot of animals imported during the year 1886, as follows.

May

PATAPSCO STATION, MARYLAND.

5 George G. Ware, Clearwater, Dak....... Liverpool..... Hereford

12

Whole number of cattle received at the various stations from January 1, 1886, to January 1, 1887.

Table showing the number of cattle received at the various quarantine stations for each month of the year 1886.

Table showing the different breeds of cattle and the number of each breed imported

during the year.

No infectious or contagious disease appeared among the animals quarantined at the above stations during the year.

Respectfully submitted.

D. E. SALMON, D. V. M., Chief of Bureau of Animal Industry.

Hon. NORMAN J. COLMAN,

Commissioner of Agriculture.

DESCRIPTION OF PLATES.

PLATE I.-Ulcerated cæcum of a pig inoculated with blood from a case of hogcholera. The entire mucous membrane has undergone necrosis. Near the valve, in the upper portion of the figure, the early stage, that of ecchymosis, is still to be seen. The valve is slit open to show the intact mucosa of the ileum. This figure also serves to illustrate the appearance presented by the cæcum and colon when pigs have been fed with pure cultures, the only difference being that in the latter case the necrosis is at first superficial. In the figure it involves the entire thickness of the mucosa, having begun in the submucosa, whither the bacteria have been carried by the blood.

PLATE II.-Ulcerated cæcum of a pig fed with viscera from a case of hog-cholera. The cæcum is slit open to show the mucous membrane quite uniformly necrosed, with isolated deeper ulcerations. The ileo-cæcal valve is very much thickened, the mucous membrane ecchymosed and ulcerated. The lymphatic glands of the meso-colon and in the angle formed by the entrance of the ileum into the cæcum are purplish, with cortex engorged with extravasated blood. They illustrate the condition of the lymphatics of both thorax and abdomen in the acute hemorrhagic form of the disease.

PLATE III, FIG. 1.-Cover-glass preparations from the spleen of a rabbit inoculated with the bacterium of hog-cholera from Nebraska. Stained for a few minutes in an aqueous solution of methyl violet, mounted in xylol-balsal. Drawn with camera lucida, Zeiss homogeneous, ocular 3. x 1110 The bacteria are seen among diffusely stained cells. They are chiefly in pairs, in some of which the process of division is not yet completed. FIG. 2.-Cover-glass preparation from the liver of a rabbit inoculated with the microbe of pneumonia in pigs. Stained in an alkaline solution of methylene blue. Mounted and drawn as stated in Fig. 1. The colored portion is confined to the two poles, the central region remaining colorless. PLATE IV, FIG. 1.-Culture twenty-eight days old in a tube of nutrient gelatine of the microbe causing pneumonia in pigs. The culture was prepared from the internal organs of a rabbit which had been inoculated from a culture obtained originally from Geneseo, Ill.

FIG. 2.-Culture eleven days old of the same microbe obtained from Sodorus, Ill.

Both natural size.

FIG. 3.-Colonies of the same microbe on a gelatine plate seven days old. x 60. The pale peripheral zone, which appears after three or four days in beef infusion peptone containing 10 per cent. gelatine, together with darker granular nucleus, is very constant.

FIG. 4.-Gelatine tube culture from the blood of a rabbit inoculated with a culture of the hog-cholera bacterium from Sodorus, Ill., ten days old. FIG. 5.-Tube culture of the hog-cholera bacterium inoculated from cultures of the spleen obtained from Sodorus, Ill., fourteen days old.

In Figs. 4 and 5 the two modes of surface growth of the hog-cholera bacterium are illustrated, both distinguishable from Figs. 1 and 2. See Plate V. FIG. 6.-Colonies of hog-cholera bacteria on a gelatine plate four days old x 100. PLATE V, FIG. 1.-Surface growth in gelatine tubes, enlarged two diameters. a. Bacterium of hog-cholera, growing as an irregular patch, flattened, with a jagged margin and occasional slender branches, and as a convex rounded head.

b. Microbe of pneumonia, growing as a very thin pearly patch, with lobed margin, often showing faint concentric lines when viewed obliquely. a, twenty days old; b, twenty-six days old.

FIG. 2.-Gelatine tube culture of a bacterium which resembles the bacterium of hog-cholera very closely, but which differs in its physiological properties, and which has no pathogenic effect on animals. Found associated with the microbe of pneumonia in the spleen of a pig (Geneseo, Ill.). Culture about a week old. The surface growth is very vigorous, covering after a time the gelatine completely. The peculiar mesh-work shown in the figure is a constant character.

FIG. 3.-Growth of the bacterium of hog-cholera on potato twelve days after inoculation.