Pathologic Anatomy and Histology. 29 



Haematopota tristis, Bigot. Latter part of May— 

 the first part of July, again in the first part of 

 September. 

 Several species of Tabanus {T. chrysurus LOEW, T. 

 trigonus COQ., T. trigeminus COQ., T. luridus 

 Fall., T. rufidens Big., etc.) July, almost simul- 

 taneously, very abundant in Aug., disappear in 

 October. 

 Inferring from the fact that in the pasturing ex- 

 periments already mentioned the disease spreads both in 

 May and June, when Chrysopus japonicus and Haemato- 

 pota tristis appear, and in July and August, when seve- 

 ral species of Tabanus develop, we can hardly avoid the 

 conclusion that those horse-flies are the real transmitters 

 of the infectious anemia among horses in Japan (vide 

 Plates III. and IV.) 



V. PATHOLOGIC ANATOMY AND HISTOLOGY. 

 A. Anatomical Changes. 



The acute and chronic cases of infectious anemia 

 among horses differ somewhat from eacji other in the 

 degree but not in the nature of their anatomical changes. 

 The usual changes are general anemia, hydraemia, ecchy- 

 moses both in the mucosa and serosa, pericardial hydrops, 

 inflammatory changes of the parenchyma, etc., and in 

 general the disease shows symptoms which are charac- 

 teristic of septicaemia. Observations on the changes of 

 various viscera and tissues of the patients will now be 

 described. 



Carcasses are usually emaciated and anemic. They 

 are, however, not so in the acute cases. Exposed mucous 



