148 TAPEWORMS OF HARES AXD RABBITS STILES. VOL.XIX. 



preserved, so tliat a number of points I have been obliged to leave for 

 further study. The present study, however, reduces the known leporine 

 forms (Andrya and Bertla excepted) to a comparatively satisfactory 

 system. 



It must be held in mind that every classification proposed for the 

 Cestoda for some years to come is experimental and provisional, for 

 helminthology is not yet so far advanced that we can tell with any 

 degree of certainty what characters or combinations of characters 

 should be looked upon as of family, subfamily, generic, subgeneric, 

 specific, and varietal value, and what characters should be attributed 

 to host-influence. 



Date of American species. " Notes on Parasites 38 : Preliminary note 

 to <A Revision of the Adult Leporine Oestodes,' ni established August 

 28, 1895, as the date of the new specific names used in this paper. 



Important notice to helminthologists. Owing to the fact that Hassall 

 and I have been using material from different helminth ological collec- 

 tions, more particularly from the collection of the Bureau of Animal 

 Industry, collection of the United States National Museum, collection 

 of Hassall, collection of Stiles, and collection of Leidy ( University of 

 Pennsylvania) bearing parallel current numbers, some confusion has 

 arisen because the same number sometimes appears in all five collec- 

 tions. These five collections were commenced independently, and as 

 their union (temporary or permanent) was not foreseen, this duplication 

 of numbers could not be avoided. 



To avoid such confusion in the future as far as possible, the collection 

 of the Bureau of Animal Industry and collection of Stiles will be cov- 

 ered into the United States National Museum, and receive the current 

 numbers of the helmiuthological collection of the Museum. 



The numbers which have been published will not be affected by this 

 change, so far as can now be foreseen. The numbers of a few of the 

 specimens Avhich have been distributed, however, will in all probability 

 be changed. Records of these specimens have been kept in the Zoolog- 

 ical Laboratory, Bureau of Animal Industry, and new labels bearing 

 the new numbers will be written and mailed to specialists and museums 

 possessing such specimens as are affected by the renumbering of the 

 collections. 



The Leidy collection, as I have stated in another publication, is depos- 

 ited with me only temporarily and will be eventually returned to the 

 University of Pennsylvania. Duplicates, however, will be kept with 

 the United States National Museum. 



Family 



Diagnosis. Cestoda with distinctly segmented strobila; head pro- 

 vided with four cup shaped suckers; rostellum well developed, or 



1 Vet. Mag., II, June, 1895, pp. 341-346, issued Aug. 28, 1895. 



