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inoculations of "virulent blood" into European or American cattle, were frequent- ly followed by disastrous results. Many of these animals die, and on performing a necropsy none of the lesions characteristic of Rinderpest, or Hæmorrhagic Septi- cæmia were found. Again, obscure diseases have appeared amongst Australian cattle in the Philippine Islands. These cattle were said to have come from a perfectly healthy and excellent cattle breeding district. On their arrival in Manila disease asserted itself almost at once. It was then found that native bred Chinese cattle are naturally immune to those obscure diseases, whereas, as already mentioned, American or European bred cattle contract these diseases naturally.

The injection of blood from a Chinese bullock into an American or European ox would also appear to induce these diseases. All these points are of the greatest moment for eattle raising industry in this Colony.

Native cattle appear to be immune to these obscure diseases. Nothing can be found microscopically in their blood, yet the injection of such blood into foreign bred animals at once induces diseases in the latter.

These obscure diseases are, so far as our present knowledge carries us, two-- Trypanosomiasis, and, what has also been found in Hongkong, Pyroplasmosis, or so-called Texan Fever. This condition was first found by us in the cows belonging to Kennedy's Dairy Farm. Full details of the outbreak of sickness amongst these animals have already been given under a saparate heading in an earlier part of the report. The repeated microscopical examination of blood films prepared from the affected animals showed the presence in the red blood corpuscles of round oval or pear shaped bodies. They varied much in size, and in fresh preparations showed amoeboid movement. By careful and repeated examination of the blood, there would exist no doubt as to their nature. We were certainly dealing with a form of Pyroplasma.

Time has not permitted us to go into details regarding the life history of such intra-corpuscular plasmodia, but with another favourable opportunity, attempts will be made, as far as possible, to study the developmental stages and mode of convey- ance of such parasites to the blood of cattle.

The experience of those working in Manila, is that true Texas Fever exists in the Philippine Islands and that a tick the intermediate host of the parasite of Aus- tralian Pyroplasmosis is present in these Islands (JOBLING & WOOLLEY). Ticks are common on the cattle housed in the various depôts in Hongkong: so far, however, our investigations in regard to these parasites are incomplete. Owing to the fact that two new diseases have been introduced into our research, it is proposed to investigate these thoroughly, previous to undertaking prophylactic and curative measures either against Rinderpest or Hæmorrhagic Septicemia. With the admix- ture of these diseases, factors of so great a disturbing nature would be introduced into our investigations that little or no hope could be held out for success along the lines of serum therapeutics. The condition of affairs has become much more complicated. Trypanosomiasis and Pyroplasmosis are diseases of signal import- ancé in regard to successful cattle breeding.

Taking up the subject of Hæmorrhagic Septicemia at this point, there remains to be mentioned several interesting pathological conditions which have been found in this disease since the date of publication of our preliminary report. The lesions, which may be set up by the Bacillus Septicemia Hæmorrhagicæ are many. There is scarcely an organ or tissue of the body, which, in a typical example of the disease, does not show pronounced pathological changes. The majority of these are constant. Others, however, vary in degree according to the severity and duration of the disorder. Such a generalised condition of affairs in the affected animals one might expect. The disease is of an intensely or septicemic or septicopyæmic nature. Many of the typical lesions found in the disease have already been dealt with in our previous report. In that report, a full description of the condition of the majority of the internal organs was tabulated and described. It is therefore unnecessary for us to recapitulate, the pathology of the intestines, stomach, lymphatic glands, etc. We would, however, direct attention to the condition met with in the lungs. The pathological lesions found in these organs in this disease would appear to vary extremely. The viru- lence of the exciting agent, the duration of the disease, etc., are factors which appear to produce very variable morbid conditions of the lungs. In regard to this ques