2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 



I believe most of the medical men who have to deal with Asiatic 

 schistosomiasis and particularly the control problem connected there- 

 with have chafed, to say the least, under the inconsistency of names 

 used in the writings of the intermediate host students. But they 

 shovild consider this to be in the nature of growing pains. 



The mixed concepts which the molluscan pages reveal are un- 

 doubtedly due to the lack of adequate material for comparative study, 

 the authors adding small fragments from time to time as these became 

 available. It seems to me that now we have sufficient adequately 

 preserved material in the collections of the United States National 

 Museum of almost all the forms to attempt an exhaustive compara- 

 tive study. 



I have given a separate historical account and discussion under 

 each genus here considered, feeling that this will prove most helpful 

 to the workers occupying the definite areas inhabited by these animals. 

 This will enable them to recognize more readily the species involved 

 in the intermediate host problem of Asiatic schistosomiasis and to 

 exonerate some innocents. 



There are many people to wiiom acknowledgment should be made 

 for helpfulness in making this endeavor as complete as it is. First 

 I should mention those who have contributed material. Among these 

 are, outstandingly. Dr. H. A. Pilsbry, of the Philadelphia Academy 

 of Natural Sciences, Dr. Fu-ching Li, of Honan University, Kaifeng, 

 Honan, China, Dr. Y. T. Yao, Director of the Central Field Health 

 Station, National Government of the Republic of China, Dr. E. A. 

 Faust, of Tulane University, New Orleans, La., Dr. H. E. Meleney, 

 Vanderbilt L^niversity, Nashville, Tenn., Dr. Sado Yoshida, Patho- 

 logical Institute, Osaka Imperial University, Osaka, Japan, Dr. 

 Mary N. Andrews, of the Henry Lester Institute of Medical Re- 

 search, Shanghai, China, and many others, particularly the early 

 molluscan collectors whose efforts are recorded with material in the 

 collection of the LTnited States National Museum, outstanding among 

 whom are von Mollendorff, Quadras, and A. Adams. 



I am also indebted to the members of my staff', Dr. J. P. E. 

 Morrison, who has made the radula and opercula preparations and 

 supervised the careful drawing thereof by our artist, Mrs. Aime M. 

 Awl, and to Dr. Harald A. Rehder for much helpfulness. 



The four genera here discussed are Blanfordia, Katayaiiia, Oiico- 

 meiania, and Schistosomophora. 



The species of Blanfordia, as far as known, are innocent of taking 

 a part in schistosomiasis. The name, however, has been erroneously 

 applied to the true menace in Japan, Formosa, and parts of China. 



