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from animal to animal, and from the observations made it seemed not improbable that the disease was carried mainly by adults, which, as nymph;:e, had engorged themselves on infective cattle.

According to the above observations the moulted nymphs, i.e., the adult forms, are most numerous in the spring and early summer months, and in the autumn months, from September onwards, which are the two periods of the year in which redwater is most prevalent.

In the same Annual Report methods for the suppression of ticks, and also for the eradication of disease caused by them, were dis­cussed. One of the methods, which has for its object mainly the suppression of ticks, is to dip their hosts in a bath containing a parasiticide. It was pointed out that arsenical dips had a more destructive action on ticks than other parasiticides. It was also stated that the best time to dip for the destruction of ticks is when the animals are likely to be carrying the greatest number of engorging females, and for the following reasons: (a) the ticks in this form remain a longer time on a host than in any of their other stages (see also Table IV.) and, therefore, a greater number are likely to be caught engorging themselves at one time; ami (b) the destruction of the females by preventing egg laying destroys the greatest amount of potential q1aterial for the provision of future generations.

It appears from the foregoing observations that dipping for the suppression of ticks should be carried out in April and May, and in October and November. It is not necessary to fix the dates more accurately, because the adult ticks are easily seen on the animals on account of their size, and farmers can judge from the number present if the best time for dipping has arrived.

The ticks should be looked for, however, at the times mentioned. To guard against the dissemination of ticks the dipping should be carried out before moving the animals from the infected country.

Another of the methods advised, which has for its object the cleansing of ticks, is to run sheep on the pastures to give the infected ticks the opportunity of discharging their virus into these animals which are naturally immune to redwater, and so divert them from cattle. It appears probable that if the sheep were pastured only for a limited period, when the infected nymph;:e are moulting-March to May, and September to November-a great deal of redwater in cattle would be avoided.

A PASTEURELLA-LIKE ORGANISM PRESENT IN AN OUTBREAK OF DISEASE IN PIGS IN NEW SOUTH WALES.

By J. BURTON CLELAND, M.D., Ch.M. (Syd.), Principal Assistant Microbiologist.

(From the Government Bureau of Microbiology, Sydney.)

AT the end of November 19IO a number of pigs in a country district died, showing extensive lesions at the time of death. In some of the specimens the skin and subcutaneous tissues were mostly affected, being invaded by diffuse purulent infiltration extending from the

GENERAL ARTICLES.

surface deeply into the sub-lying tissues. There was considerable cedema around the infiltration. The ears and trotters were bright pink. The lungs showed extensive areas of collapse, but no definite broncho-pneumonia. In places were scattered petechial extravasa­tions under the serous coats and in the tissues. The stomachs of two cases showed considerable congestion, of the fundus especially; in one there was present an intense h;emorrhagic condition in this situation. The lesser curvatures were unaffected. One specimen of small intestine was in part deeply congested. Some enlarged lym­phatic glands from one case were also submitted, but the situation from which they came was not stated. These showed areas the size of small peas or smaller, containing foul-smelling, yellowish, caseous­looking pus or a thin purulent fluid. Smears from the lungs showed in one case one doubtful bipolar bacillus. Preparations from a spleen were negative. Pus from the purulent areas of the enlarged lymphatic glands showed large numbers of bacteria; about half of these were small Gram-positive bacilli, and the other half small Gram-negative bacilli of several kinds, some of them bipolar. In the non-purulent areas of these glands the bacteria were much fewer, and were small doubtfully bipolar Gram-negative bacilli, sometimes free, sometimes in groups in the polymorphonuclear cells.

Pig .No. I.-Cultures from the lung gave some white colonies of small Gram-negative bacilli. A rabbit was inoculated with this culture. and died in nine days with an extensive area of yellowish exudate and cedema at the site of inoculation. The liver and heart were congested, and the spleen a little congested. Smears from the site of inoculation showed a number of swollen bodies like degenerated organisms. From the heart. liver, and inguinal region cultures were made, and showed, besides some large colon-like colonies, some smaller white ones. These smaller white ones appeared identical with those originally obtained from the lung and used for the purpose of inoculation of this rabbit. They consisted of small Gram-negative bacilli, somewhat bipolar, resembling one of the pasteurellas. They were non-motile. On agar they gave a uniform moderately dense white growth, decidedly more abundant than in the case of the rabbit pasteurella. Gelatine was not liquefied up to three weeks; the organism on sugar media gave acid in glucose and iu cane sugar, but not in mannite, dulcite, or lactose. The cultures obtained thus from the rabbit were inoculated into a second rabbit a month later. This rabbit died in two days, but, unfortunately, through an oversight no post-mortem was held.

Seven weeks after isolation from the first rabbit, a broth culture was injected into a third rabbit. This died in four days, and showed a large necrotic area at the site of inoculation. The intestines were slightly congested, but there were no other lesions. Smears from the inoculated point showed numerous Gram-negative, pasteurella­like organisms, and in those of the heart-blood, liver, and spleen similar, but fewer, organisms were found. Cultures resembled the original ones.

pzg No. 2.-N umerous cultures were made from the large glands, with and without pus, from the spleen, from the lung, and from the skin. Numerous or.ganisms of different kinds were obtained in the cultures, the most numerous being minute Gram-negative cocci. These were

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obtained from the large gland where there was no pus, and from the skin. On inoculation, the small cocci were found to be non-patho­genic to a guinea-pig and to a pig. From the mesenteric glands of this case organisms belonging to the colon group, producing acid and gas on some sugar media, were obtained. The pasteurella-like organism was not obtained directly from the lesions. A guinea-pig was inoculated with loops of fluid from the large gland where there was no pus. It died in a fortnight, and showed the presence of an abscess the size of a walnut at the site of inoculation, but no other post-mortem lesions. Cultures made from the abscess were overgrown by Gram-positive cocci, some white and some golden, and on re­plating only these organisms were obtained. Smears from the inguinal region showed the presence of small bipolar bacilli from the abscess; these small bipolar Gram - negative bacilli were numerous. There were also larger Gram-negative bacilli and Gram­positive cocci. Smears from the liver and heart - blood showed nothing.

The interest of these cases lies in the isolation from one of them of an organism apparently related to, though in some important particulars different from, the pasteurella group of bacteria. In the other case, though this organism was not isolated, it was apparently detected in smears from the organs of the infected pig, and in smears from the organs of the guinea-pig inoculated with material from this pig. The chief point of difference between the organism isolated and the pasteurella group consists in its more abundant growth on agar, and in the fact that it produces an extensive necrotic area at the site of inoculation in rabbits. Its morphology and sugar re­actions link it up with the pasteurella group. The latter results, on the five sugars tested, agree absolutely with our laboratory strains of rabbit pasteurella (three sources), pig pasteurella (Kral), cat pasteur­ella, rat pasteurella, one isolated from a contaminated pleuro-virus, and a New South Wales pig pasteurella. Of sixteen strains of bacillus pestis isolated from various sources (human, rats, marsupial) during the last ten years, all gave acid on glucose, one gave acid in saccharose after eight days, and two-of great interest, as apparently representing a mutational change of the organism in a small epidemic -gave acid in mannite. Considerable difficulty was experienced in working at these cases owing to a marked degree of secondary and putrefactive infection being also present.

THE EFFECT OF NUCLEIN ON THE BLOOD.

By B. F. KAUPP, M.S., D.V.S., Professor of Pathology, Div. Vet. Sci., Colo. State College, and Pathologist to the Colorado Experiment Station, U.S.A.

NUCLEIN is an organic body contained within the nuclei of cells. It is acid in reaction. In composition it has been placed between proteid and nucleinic acid. It contains from 3 to 10 per cent. phos­phorus. When combined with albumen it is sometimes spoken of as a nucleo-proteid. Physically it is an amorphous substance. On boiling with alkalies phosphoric acid is set free. After the isolation