SYNOPSIS OF THE TREMATODE FAMILY HETERO- 

 PHYIDAE WITH DESCRIPTIONS OF A NEW GENUS 

 AND FIVE NEW SPECIES. 



By Bratton Howard Ransom, 

 Assistant Custodian, Helminthological Collections, United States National 



Museum. 



The family Heterophyidae is composed of a number of genera of 

 small flukes, parasitic in the intestine of mammals and birds, usually 

 fish eaters. The family is of considerable interest in human and 

 veterinary medicine as several species are of more or less common oc- 

 currence in man, dog, or cat. The following genera may be recog- 

 nized as belonging to this family : Heterophyes Cobbold, 1866 ; Cryp- 

 tocotyle Liihe, 1899 ; C entrocestus Looss, 1899 ; Ascocotyle Looss, 1899 ; 

 Apophallus Liihe, 1909 ; Pygidiopsis Looss, 1907 ; Metagonimus Kat- 

 surada, 1913; a heretofore undescribed genus proposed in the 

 present paper; and, provisionally, Paracoenogonhnus Katsurada, 

 1914, a very imperfectly known genus possibly identical with Gryp- 

 tocotyle. The following generic names in this family either fall as 

 synonyms or are not to be recognized at present because the species 

 upon which they are based are considered to belong to some of the 

 genera of prior date : 



Coenogonimus Looss, 1899 (type heterophyes) , and Gotylogonimus 

 Liihe, 1899 (type heterophyes) are both synonyms of Heterophyes. 

 Tocoi^rema Looss, 1899 (type Zm^wa), and 5'a^Zi^mWigdor, 1918 (type 

 caninum), are congeneric with the earlier Gryptocotyle Liihe, 1899 

 (type concava). Tocotrema and Gryptocotyle are based on different 

 type species, but the differences in these do not appear sufficient to 

 justify their generic separation, while HaXlum caninum appears to be 

 specifically identical with Gryptocotyle lingua. Loossia Ciurea, 1915 

 (type romanica), and Yokogawa Leiper, 1913 (type yokogawa= 

 yokogawai)y give way to Metagonimm Katsurada, 1913, Leiper's 

 genus being based on the same type as Metagonirrms and Loossia 

 clearly having the characters of Metagonirrms. 



The genus Scaphanocephalus Jagerskiold, 1903 (type and only 

 known species expansus), has been considered by some authorities 



Proceedings U. S. National Museum, Vol. 57— No. 2322. 



527 



