PEOCSEDINGS OF SECTION D. 



273 



European. 



Brachyccelium, 

 one species. 



Prosotocus, 



Pleurogenes, 



Brandesia, 



•even species in all. 



Diplodiacus. 

 one species. 



Oorgodera, 



Gorgoderina, 



five species each. 



Polystomum, 

 one species. 



Am-ricAn. 



Australian. 



In the Intestine — continued. 

 Sub. -f am. Brachycoelinae. 



Brachyccelium, 

 one species. 



Mesocceliutn, 

 three species. 



Sub.-fam. Pleiuogenetinse. 



Loxogenes, 

 one species. 



Pleurogenes, 

 two species. 



In the Rectum. 



Fam. Paramphistomidse. 



Diplodiscus, \ Diplodiscus, 

 one species. | one species. 



In the Bladder. 



Sub.-fam. Gorgoderinse. 



Gorgodera, 

 one species. 



Gorgodera, 



Gorgoderina, 



five species each. 



Sub.-fam. Polystominae. 



Polt/stomum, 

 one species. 



(Polystomum), 



two species in 



chelonians. 



Asiatic. 



Mesocoelium, 

 one species. 



Pleurogenes, 

 two species. 



The small number of representatives iu the Asiatic group is accounted 

 for by the fact that up to the present comparatively little attention has 

 been given to this group by investigators. 



The various species of the same genus iu each case are very closely 

 related to one another from the morphological point of \new. The 

 differences between them are only small, so small that for a longtime 

 they were not recognised at all, but the flukes were identified, in some 

 cases, under the name of the oldest known species of the genus in 

 question. The differences were concerned with such points as size and 

 shape, the amount of spininess, the relative size of the suckers, 

 the relative size and shape and small alterations in position of some of 

 the internal organs, and the size of the eggs. 



