204 GARRISON. 



Therefore, the conclusion would appear to be warranted that infection 

 with lung flukes is not evenly distributed throughout the Philippines, 

 as appears to be the case with the parasites above considered, but that it 

 is to be found chiefly in the southern portions of the Archipelago. 



It is quite within the bounds of probability that the distribution of 

 this parasite may be found to be even more strictly localized. To the 

 best of our knowledge, all cases of paragonimiasis reported for the 

 Philippines, in which the history of previous residence was known, have 

 originated in the southern part of the Islands, and further investigation 

 may show the infection to be confined to this region. The possibility 

 can not be excluded that the infection is limited more or less strictly to 

 certain of these southern islands. Some indication of this was found 

 in our own figures. For instance, 239 prisoners from the Island of 

 Leyte were examined and 6 had paragonimiasis; 127 prisoners from the 

 Island of Samar gave four infections with lung flukes ; on the other hand, 

 while 248 prisoners from Panay were examined, no fluke infections 

 occurred. However, until the matter has been further investigated, we 

 believe that the only generalization justified by our results is as already 

 stated : namely, that paragonimiasis prevails in the southern rather than 

 in the northern parts of the Philippines. 



INFECTIONS WITH SCHISTOSOMA JAPONICUM. 

 (0.6 per cent.) 



The use of the specific name seems desirable in the present case in 

 order to differentiate Schistosoma japonicum from S. haematobium, all 

 of our infections being with the former species. 



Geographical distribution. — As in the case of Paragonimus, the ap- 

 parently uneven geographical distribution of Schistosoma infections 

 appears to be of greater interest and importance than the actual percent- 

 age of infection found among the prisoners examined. The cases of 

 schistosomiasis were distributed geographically as follows : Manila, 1 ; 

 Samar, 6; Leyte, 5; and Mindanao, 4. Therefore, excepting the one 

 case from Manila, all infections with Schistosoma appear to have origi- 

 nated on the three southern islands, Samar, Leyte, and Mindanao. 



INFECTIONS WITH OPISTHORCHIS. 



(0.3 per cent.) 



Racial and geographical distribution. — In only five of the eleven cases 

 of opisthorchiasis could a definite history of previous residence be ob- 

 tained. Three of these came from the Island of Mindanao, one from 



