632 On Flagellated Organisms in the Blood of Animals. [part hi. 



a particular room would be affected, " whereas the blood of rats in another part of 

 the building would not contain them. The servants had ultimately come to recognise 

 this, as, whenever they learnt that a particular rat's blood contained the desired 

 organisms, they diligently endeavoured to secure the rest of the family," so that the 

 possibility is not absolutely excluded that the finding of these parasites in the blood 

 of the puppy and of its mother may have been a coincidence and not the direct 

 result of the experiment ; nor is it knowA to what extent the blood of horses and 

 camels or other animals in this part of India [Madras] may harbour these organisms 

 or may have harboured them at that time. 



These flagellated blood-parasites are not, however, limited to India, for in 1881 

 Wittich described similar organisms in the blood of hamsters in Grermany.* Wittich's 

 experience coincided with my own as regards their being found in the blood of 

 apparently perfectly healthy animals, though Dr. Robert Koch,t instigated by the result 

 of Wittich's observations, found that the hamsters which he procured died, one within 

 two days of being in captivity, and four others subsequently. It does not appear 

 that the blood of these hamsters was examined during life, but after death it was 

 found, in each case, to contain the organisms in question. No reference is made to the 

 examination of other hamsters, so that it is not quite clear whether the animals died 

 as a result of captivity or in consequence of the parasitism. As regards rats thus 

 afifected I have had them kept in a cage for weeks, and to all appearances in a 

 state of perfect health. Both Wittich and Koch suggest that the parasites found by 

 them in the blood of hamsters are in all probability identical with those found by 

 me in rats in India ; and Koch gives two micro-photographs of them which correspond 

 very i closely with the micro-photographs which were published by me in the previously 

 mentioned Indian " Sanitary Report." 



What these organisms are and whence their origin is by no means clear, and as 

 the suggestions which have been offered by various authorities regarding these points 

 are so greatly at variance it seems highly desirable that every detail which can be 

 collected concerning them should be placed on record. This is all the more to 

 be desired, seeing that the question has arisen of their possible influence as a cause 

 of disease. 



I had every opportunity of satisfying myself that the parasite found by Dr. Evans 

 in the dog is identical with that in the rat, as Dr. Evans brought the puppy 

 to Simla in October, 1880, and very kindly made it over to me for observation. 

 The accompanying sketch represents some of the forms assumed by these organisms 

 as observed under a Prazomwski's 1*5 mm. immersion objective. This, together with 

 the following remark, made at the time, are copied from my note-book : — 



A drop of blood having been obtained from the puppy's ear about 9 a.m. on the 

 26th October, it was found to contain a considerable number of these organisms in a 



* Centralblatt fUr die medicin. Wissensch., vol. xix, No. 4. 



f " Mittheilimgen aus dem Kaiserlichen Gesundheitsamte," vol. i, p. 9, 1881. 



