ABSTRACTS. 73

2. Typical distemper may be induced in susceptible dogs by infection under perfectly controlled conditions with pure cultures of bacillus bronchi­septicus, utilising methods simulating natural modes of transfer of the disease, and the bacillus may be recovered in pure culture from the organs of such experimental cases.

3. Dogs which have recovered from attacks induced by this bacillus are protected on exposure to natural distemper, and susceptible dogs actively immunised by subcutaneous injections of small doses of this bacillus become immune to natural distemper. (Torrey and Rahe, Journ. Med. Research, Vol. XXVI!., NO.3, January 1913, pp. 291-364.)

EXPERIMENTAL AMCEBIC DYSENTERY AND LIVER ABSCESS IN CATS.

IN the early portion of this paper the author discusses the question of the identity or otherwise of entamreba tetragena and entamreba histolytica, the former described by Viereck and the latter by Schaudinn as the common pathogenic amreba of man. It appears to be probable, and the author's own experience confirms the view, that in reality the two parasites are the same, but that Schaudinn was in error in his description of certain stages of the organism.

The experiments carried out with cats were conducted with material obtained from a case in a European from Bombay in which numerous free and encysted amrebce occurred. About 5 cc. of fceces containing amrebce were iniected per resophagum and per rectum into two cats. Both contracted dysentery, and nineteen days later were passing large numbers of amrebce. It is probable that they had been passing them for some days previously. It has been shown by a number of observers that the ingestion of amrebce alone by cats will not cause dysentery, but that the ingestion of encysted forms will. (Intrarectal injection of amrebce will produce infection.) From these cats others were infected, and the author carried on the infec­tion through four passages without any apparent loss of virulence, but owing to an accident he was unable to carry it further. The method of trans­mitting the infection from cat to cat was to wash out the ulcerated large intestine with salt solution, which was then used for injection into the large intestine of the next animal. It was found to be advisable to use kittens soon after they have become independent of their mother.

In addition to the production of ulceration of the large intestine, generally in the lower portion, the author has found the glands of that portion of the intestine invaded by amrebce and to a great extent destroyed.

A cat of the fourth passage, in addition to developing typical ulceration of the large intestine, developed abscesses containing amrebce in its liver. In all there were four abscesses, the largest of which measured half a centimetre. The fact that it was a cat of the fourth passage that developed the liver ab~cesses indicates that there had been no loss of virulence.

It is difficult ~f) decide exactly how the amrebce find their way {rom the intestine to the liver. The author states that it would most probably be by way of the portal blood, and this is perhaps borne out by the fact that one cat developed pycemia, in which the whole of the blood-system contained pus. The possibility of invasion by way of the lymphatics is pointed out, as the author ha~ observed involvement of the intestinal glands.

The process of invasion of the gut wall may be studied in sections.

74 ABSTRACTS.

The amrebre make their way to the bottom of the tubular glands in the large intestine. There they multiply, and by pressure of their numbers or by the exertions of their pseudopodia, and probably through some toxic substance secreted by them, the linmg cells are weakened and separated, allowing the amrebre to penetrate between them.

The epithelial ceI\s commence to degenerate, and this is followed by bacterial invasion, the amrebre in the meantime penetrating into the deeper layers and producing the characteristic undermined ulcers.

No detailed description of the parasite is given, but mention is made of the fact that the author has not been able to find encysted forms in the freces of cats. This is probably accounted for by the fact that the dysenteric process in cats does not pass beyond the acute stage. In man, cysts are rarely seen in the acute stages. Should cats commence to recover from the acute stage of the disease it is possible that encysted forms would appear in the freces.

Experiments carried out with entamreba coli and another small amreba occurring in the freces of a native of India had negative results, although enormous numbers of amrebre were used. This is a further proof that in man both pathogenic and non-pathogenic amrebre occur. (Wenyon, Journ. London School Trop. Med., Vol. II., Part I, December 1912, pp. 27-34.)

AN OBSCURE DISEASE OF MULES.

THE following is an abstract of a Report on the occurrence of an obscure disease observed among mules at Naseli, Fiji.

The animals were found to be suffering from lymphangitis associated with cording of the lymphatics of one or more legs. Abscesses were observed on the course of the lymphatics, which appeared to be cold and painless, and resembled small subcutaneous fibromata. These lesions were quite freely moveable under the skin. Only a small percentage showed any tendency to burst, and in cases in which this happened a small quantity of white creamy pus was discharged. Some of the abscesses showed signs of healing. The principal situation of the lesions was on the inner surface of the thighs and hocks, and they varied in size from a pea to a hen's egg.

Two of the affected mules had a profuse blood-stained tenacious discharge from both nostrils, and ulcers as large as florins were discovered on various portions on the nasal mucous membrane. In about 50 per cent. of cases there was no evidence of submaxillary adenitis, the temperature was only slightly elevated, and the animals were feeding well. The lymphangitis was associated with considerable lameness.

The animals were tested with mallein but failed to react. Pus from an unruptured abscess was searched for the cryptococcus of Rivolta without success.

A post-mortem was made on one of the mules which died and the following lesions found: Gangrenous pneumonia of both lungs, but no nodules. Extensive ulceration of the mucous membrane of the nose, with complete perforation of the septum. There was ulceration of the larynx, but none in the trachea. The facial sinuses were healthy. The lymphangitis was due to a straw-coloured exudate, and the abscesses had very thick walls, varying from half to one inch in thickness.

In all, three post-mortem examinations have beep made. The gangrenous pneumonia was not constant, and in two cases there were small abscesses in