NOTES ON PARASITES (^) 



48. — AN INVENTORY OF THE GENERA AND SUBGENERA OF THE 

 TREMATODE FAMILY FASCIOLIDAE 



CH. 'WARDEL.L STILES AND ALBERT HASSALL 



Various attempts hâve been made to classify the numerous spe- 

 cies of Trematodes belonging to the family Fasciolidae, and quite a 

 number of gênera and subgenera hâve been proposed. Thèse 

 attempts hâve not been altogether satisfactory, not we believe 

 solely because of the difficulty of the problem, as some helmintho- 

 logists seem to assume, but rather : First, because authors hâve in 

 many cases failed to designate type species for their gênera ; on 

 this account some of the groups bave not had any standard of 

 référence, and as a resuit authors bave relied upon diagnoses not 

 well founded. Second, too little attention bas been paid to topo- 

 graphical anatomy and homoplasy. Third, new groups bave been 

 proposed without a critical study of the gênera already established. 



It appears to us that excellent characters exist for several of the 

 généra, and as soon as more of the forms are studied in détail, we 

 believe the entire family may be reduced to a comparatively satis- 

 factory System. 



During our studies of some of the members of this family para- 

 sitic in the domesticated animais, it bas been necessary for us to 

 trace the original références of a number of the gênera, and noticing 

 that in some cases their types bave never been chosen, we bave 

 been obliged to designate sucli generic types. At the same time we 

 bave endeavored to test the proposed gênera and subgenera by 

 analytical keys (a valuable method too often neglected in helmin- 

 thology), and to suppress several synonyms and homonyms. 



This study, undertaken entirely from a standpoint of économie 

 and practical helminthology, has naturally involved considérable 



(1) Publishcd by autliority of Dr. I). E. Salinon, Cliicf of the Bureau of Ani- 

 mal Industry, U. S. Department of Agriculture. 



Archives de Farasitolo(jic, 1, n" 1, l«y!S. H 



