654 
ED. NOCARD. 
Here are instances taken from the pathology of animals. 
Texas fever, or bovine malaria, is a disease widely spread 
over the globe ; central Europe is perhaps the only region free 
from it. 
It is also a disease caused by a parasite of the corpuscles of 
the blood. This disease, very different from the other, is in¬ 
oculated to animals not by mosquitoes, but by another insect of 
the great family of ixodes, vulgarly called ticks. It is the tick 
which with its sting deposits in the blood a small number of 
parasites which multiply with such prodigious rapidity that in 
some cases, a few days after this inoculation, the number of red 
corpuscles, which in a healthy animal is over eight millions 
to a cubic millimeter, drops to less than one million. All the 
invaded corpuscles are dissolved, the urine becomes bloody or 
dark and animals die in a few days. Cattle can be protected 
by various means. One which seems the simplest would be to 
stop the importation of animals from the countries where the 
disease exists ; if they are already imported they must be 
cleaned of the ticks that are on them. Once free from those 
parasites those animals are no longer dangerous, unless ticks 
come again on them. Other means can be used to prevent 
bovine malaria. For instance, infested regions can be made 
healthy by changing the cultivation of the soil from natural 
to artificial fields, where it seems ticks cannot develop. Finally, 
my assistant, Mr. Eignieres, has shown that it is possible also to 
protect cattle by a process of true vaccination. 
Another disease unknown in our countries, but which has a 
certain interest of actuality, is the “ Horse Sickness ” of South 
Africa, which did so much harm to the English army at the 
beginning of the war. Its nature is not known, but it attacks, 
almost fatally, all the horses which are recently imported into 
that country. Those which are not acclimated, that are not 
u salted,” as the Boers say, are in general lost; however, if they 
resist a first attack, they are protected forever and they become 
very valuable. This disease is not contagious. During the 
winter the disease can be inoculated to an imported horse and 
