50 DR. T. S. COBBOLD's SYNOPSIS OT THE DISTOINHD^. 



Trematodum, sp. Ley dig. 



Hab. Found in abundance by Leydig in the cranial cavity of Cobitis 

 fossilis. 



4. DiPLOSTOMA, MiiLLERi, Cobbold. 

 D. Petromyzi fluviatilis, Miiller. 



D. rachiceum, Miiller ? 

 Tylodelphys ? Diesing, Revis. p. 12. 



Hab. Found by Miiller in abundance in the cerebral cavity of Petromy- 

 zon fluviatilis. 



5. DiPLOSTOMA cuTicoLA, Diesing. 



D. cuticola, Diesing, Revis. p. 13 ; Leidy. 



Hohstomnm cuticola, Nordmann, Gescheidt, Dujardin, Creplin, Siebold, 

 Wigham. 



Hab. Found by Nordmann in Leuciscus Idus, L. erythrophthalmus, and 

 L. rutilus ; also by Wigham and Siebold in the last-named species ; 

 by Siebold likewise in L. Dobula, Phoxinus lavis, and Gobio vulgaris ; 

 by Nordmann in Cyprinus Carpis, Abramis Brama, and A. Blieca; 

 by Creplin in A. Virnba ; by Kollar in Cliondrostonia nasus; by Leidy 

 in America in Pomotis vulgaris. It generally occurs encysted beneath 

 the skin and internal mucous surfaces ; Leidy found it in the liver. 

 According to Von Siebold, this species arrives at maturity in the intes- 

 tinal canal of certain Water-birds. 



6. DiPLOSTOMA voLVENS, Nordmann. 



Diplostomum volvens, Nordmann, Gescheidtj Dujardin, Creplin, Aubert, 



Claparede, Diesing; Revis. p. 13. 

 Hab. Found by Nordmann, and others, in the eyes of Acerina vulgaris, 

 P ere a fluviatilis, Lucioperca Sandra, Leuciscus erythrophthalmus, and 

 LiOta communis ; by Creplin in hota communis and Leuciscus rutilus. 

 According to Steenstrup, this form, D. cuticola and D. clavatum, are 

 identical ; yet no one of the three species can with certainty be regarded 

 as a mature trematode, the true adult representative having still to be 

 sought among the Holostomata. 



7. DiPLOSTOMA BREVICAUDATUM, Diesiug. 



D. brevicaudatum, Diesing. 



Holostomum brevicaudatum,, Nordmann, Gescheidt, Dujardin. 

 Hab. Found by Nordmann free in the vitreous humour of Barbus 

 communis. 



8. DiPLOSTOMA GRANDE, Diesing. 

 D. grande, Diesing, Revis. p. 14. 



Hab. Found by Natterer in Brazil in the intestines of Ardea Leuce and 

 A. Agami. 



We are surely entitled to regard this species as an adidt form, after 

 consulting Diesing's description and figures as given in his ' Neunzehn 



