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Unfortunately the animal was cremated before microscopic examination showed the nature of the disease. No chance was given to prosecute the study of the malady any further. It has been found advisable to cremate animals as shortly after death as possible, as decomposition sets in very rapidly in this climate and it is highly inadvisable to have such carcases in the vicinity of cattle depôts and a slaughter- house.

Had it not been for the systematic microscopic examination of the blood of all cattle found dead in the Depôt, this important result would undoubtedly have been missed. Should time permit in the future, it is our intention to undertake a more or less systematic examination of the blood of the live cattle in the different Depôts of the Colony and determine as far as possible the extent of possible Trypanosomi- asis existent. Judging from the results of other investigators, especially of those working in Manila, the most satisfactory conclusions will be obtained by the use of experimental methods. The employment of European bred cattle and of ordinary Laboratory animals for experimental purposes will undoubtedly assist us in deter- mining the extent of such a disease amongst our herds in the Colony.

Guinea pigs, rats, mice, horses, etc., are said to be immune to cattle Trypanoso miasis. Calves, according to THEILER, are very susceptible. At the same time this single case is, in our opinion, a sufficient guarantee of the existence of the disease in our midst and the experience of American workers in Manila to where hundreds of cattle are exported from Hongkong, adds considerable weight to our convictions. Like the result obtained in the Philippines, our conclusions will probably have to be gauged by animal experimentation. Cattle Trypanosomiasis is a disease which may be either acute or chronic. Different infections are apparently influenced by a varying virulence of the parasite. There would appear to be little doubt that occasionally the disease may run an epizootic course with a high mortality, whereas in other outbreaks the disease, may be more of a chronic nature, the animals becoming gradually emaciated with an intermittent temperature. The mortality in these chronic cases is low.

The facts bearing upon the variations in the acuteness of the disease are by no means well known. The scientific facts regarding Trypanosomatic and allied diseases are as yet few, rendering the expression of an opinion as to the significance of the disease a question of extreme difficulty; however, this much may be said that the presence of Trypanosomiasis in cattle in Hongkong is an additional factor of grave import in any attempt at making cattle breeding in the New Territory a lucrative industry. Since the commencement of our researches into cattle diseases in the Colony we have constantly borne in mind that probably in Chinese cattle Rinderpest represented not one disease but a group of diseases.

Indeed we have been able to find few instances of typical Rinderpest as classi- cally described in books. That such a disease exists in China there would appear to be no doubt, but that true Rinderpest is the commonest manifestation of sickness amongst the cattle in this Colony is by no means obvious.

In our preliminary report we distinguished true Rinderpest from a disease known as Hæmorrhagic Septicænia. The latter would appear to represent a group of diseases much alike in etiology, symptomatology and pathology. Our observations in this respect have been amply confirmed by the workers in the Biological Laboratory in Manila where the same complex diseases are frequently encountered.

At the time of publication of our preliminary report we were inclined to think that, in all probability, this Hæmorrhagic Septicemia was the commonest cause of disease amongst cattle in Hongkong. It appears to be the factor at work in the production of these epizootic outbreaks which occur from time to time. Again, it appeared obvious that to deal with the disease effectively, some method of preven- tive inoculation would require to be prepared. During the past year a considerable literature has sprung up around the subject of Rinderpest and Hæmorrhagic Sep- ticæmia. The researches of South African and Philippine investigators have shown that during the course of immunisation of cattle against so-called Rinder- pest, other diseases asserted themselves, the cause of which appeared to be traceable to the results of inoculation of "virulent blood."

It has been generally found that the inoculation of "virulent blood" into native bred cattle is followed by mild reactions of a non-lethal nature. Similar

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