WATAXABE : ON THE SO<--\LLED BLACK HEAD OF TURKEY. 77 



the morphological harmony of the parasite observed by Smith with that by myself, 

 it differs in size : the parasitic protozoön in my case is smaller, as compared with 

 that ill the case of the American observer ; this difterenc is, however, due, it is 

 probable, to the different reagents of fixation employed in both the cases. A fiirther 

 difference in the results by Smith from mine consists in the frequent occurrence of 

 the exudates on the outer surface of the diseased ccecum, while this is not the case 

 in tlie sptcimens obierved by myself. I have never met witli at all any structure 

 which may answer to the giant cells mentionetl by Smith : they are, I think, nothing 

 else than the thickly grouped parasitic cells imbedded in the destroyed tissues. 



From the sccoimts given above, the mortal cause of the host is not difficult to 

 inter. In the ctise in wliich tlie hotft dies when the cceca alone are attacked, the 

 death is due to diminisheii absorption of the digested matters ; for the ooeca of the 

 birds form, hs is very well known, a strong organ of absorption. The death in the 

 ca^e of the disease attacking the liver is self-evidently causetl by the weakene«! hepatic 

 fnnctron. Verv common mortal causes consist in destruction of both the orarans. 



Among others, Schaudinn worked out Entamcfb^i hydolyca occurring in the 

 human Ixnly. It is in great resemblance with the paraäte of the turkey above 

 mt^ntionetl. A com])arative study of the parasites in both the hosts will prove of 

 interests. 



It h the common opinion in our country, that turkey farming is connected 

 with great difficulties, and we liave been informed that the difficulties consist chieflv 

 in protecting the bird from the disease above referreil to. To d«) this, we have only 

 t" kfop off the chicken from the infected individuals. » 



Summary. 



1. Ti.e disease i.-? eaustd by the parasite called Amaba sp., and not by bacteria 

 fJnnd in the coecii. 



2. The parasite attacks first the civoa. the histolosrical .structure «.f wlnVh is 

 destroyed by it. 



3. Some of the parasitic organisms escape from the cceca through the Lieber- 

 killin's crypt, into which it comes out, bre:iking up the crypt*s walls. 



4. Passing through the portal vein, it comes then to the liver which is c-on- 

 verted by it at last into hai-d plates. 



Ö. The parasite escapes from the liver through the bile-«luets. 



(j- The panisite from the liver, t«rether with that from the cceca, is cast off 



