Among Horses in India. 79 



papillosa and other nematodse were found in the mesentery, 

 and in some the mucous membrane of the intestines was 

 yellow, and marked with petechise. 



Possibly caused by Flies. — There is no evidence that the 

 disease is contagious or infectious in the ordinary acceptation 

 of those terms. The natives believe that it is caused by a 

 large fly about the size of an English gadfly, which is common 

 in the country, and which bites the legs of horses until the 

 blood flows down them in streams. Dr. Evans thought that 

 possibly these flies might convey the poison by biting one 

 horse before the blood which they had extracted from another 

 had dried upon their mouths. 



Animals Subject. — Mules and camels are subject to the 

 •disease, but horned cattle and donkeys are said to be exempt. 



From a series of experiments, Dr. Evans found that a 

 healthy horse becomes afl'ected if the blood from a diseased 

 •one be either swallowed or injected under the skin. 



Inoculation. — When inoculated in the latter manner the 

 first external signs of the disease appear on the fourth day, 

 and on the sixth the blood is swarming with parasites of a 

 peculiar kind. When the blood was given to drink, the first 

 signs of illness were seen on the fifth day, and the parasites 

 on the seventh. 



These parasites are apparently round, tapering in front to 

 a neck, ending in a blunt head. They are white in colour, 

 with active eel-like motions, and seem to be about three or 

 four times the diameter of a white corpuscle in length and 

 one-tenth the diameter in breadth. They appear to live upon 

 the red corpuscles. 



Changes in the Blood. 



In the early stages of sickness, the blood firstly has a 

 greatly increased proportion of white corpuscles ; secondly, a 

 large number of the red corpuscles changed into shapeless 

 particles of pale red jelly ; and thirdly, a large quantity of 

 small granular particles floating in the serum. 



Mr. Evans believes that the parasite is derived from the 



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