ANTHRAX : PREVENTIVE INOCULATION IN LOUISIANA. 
645 
and where these conditions are absent no tabanidse are observed.” 
All such' favorable conditions we possess in abundance in 
the sections of Louisiana which suffer most from anthrax. 
For instance, at the back of many of our plantations are woods 
and moist places, such as swampy lands, and it is to those un¬ 
cultivated portions of the properties that the remains of all 
animals have been committed. All carcasses have been treated 
alike, whether charbonous or otherwise, viz.:—dragged or hauled 
out to the “ bone yard,” and there left, exposed on the surface 
of the ground. This practice has been in operation almost from 
time immemorial (although it is now changed for the better in 
most places), with the result that infection has been yearly 
added to the surroundings. Now, we find that first cases usually 
occur amongst animals, frequently cattle, in the neighborhood 
of these infected areas. With the development and multiplica¬ 
tion of the flies, and the blood of the first victim at hand to feed 
upon, it may readily be inferred how the infection is scattered 
broadcast. 
t 
It has generally been observed that outbreaks of anthrax, in 
epizootic form, in Louisiana, usually succeed protracted seasons 
of drought in summer, and, after the breaking of such drought 
by the first few showers of rain. On the other hand, the disease 
rarely occurs over an extended area, and if at all, in only 
sporadic or enzootic form, during seasons in which we have fre¬ 
quent and copious precipitation. This may be accounted for, 
first of all, by the fact that a lengthened dry spell of weather 
favors the development and multiplication of greater numbers 
of horse-flies, many of which would be destroyed in the oval or 
larval stages by incessant heavy rains during these more delicate 
stages of the insect’s life. 
Then, again, the moisture from the showers, following the 
dry weather, combined with the natural heat of our summers, 
brings about conditions favorable to the development of latent 
bacterial life already in existence in infected localities. 
When heavy and frequent rains continue during our sum¬ 
mers, we seem to have fewer of these flies, for the reasons, no 
