58 CATALOGUE OF ENTOZOA. 



23. Distoma microcephalum, Baird. (Tab. II. f. 2.) 



Body of an elongated oval or lanceolate shape, of a slightly yel- 

 lowish-white colour, plicated transversely, the folds being very 

 fine ; head narrow, obtuse, separated from the body by a con- 

 traction ; posterior extremity obtusely lanceolate ; dorsal sur- 

 face slightly convex ; ventral surface nearly flat, or somewhat 

 concave ; anterior sucker small, terminal ; ventral sucker 

 larger, round, prominent, and surrounded by an elevated, 

 thickened edge, and situated within 3 millimetres of the 

 former ; organs of generation placed halfway between the two 

 suckers, and in form of an elevated papilla. 



Length from 6 to 8 lines, greatest breadth 1^ line. 



Hab. Stomach of the Spinous Shark, Acanthias vulgaris. From 

 Falmouth Harbour. 



From the collection of W. P. Cocks, Esq. 



24. Distoma isostomum. 



Distoma isostomum, Rudolphi, Synopsis Entoz. 105 & 392, n. 62 ; 

 Creplin, Nov. Obs. de Entoz. 64 ; Baer, Nov. Act. Acad. Cois. Nat. 

 Cur. xiii. 553 ; Dujardin, Hist. Nat. Helminth. 471 ; Diesing, 

 Syst. Helminth, i. 363. 



Hab. Ganglions in the common Cray-fish, Potamobius astacus. 

 From the collection of M. Siebold. 



25. Distoma cirrigerum. 



Distoma cirrigerum, Baer, Nov. Act. Acad. Nat. Cur. xiii. 553 ; 



Dujardin, Hist. Nat. Helminth. 472. 

 Distoma isostomum ? Diesing, Syst. Helminth, i. 363. 



Hab. Hydatid tumours of the common Cray-fish, Potamobius 

 astacus. 



From the collection of M. Siebold. 



26. Distoma holostomum. 



Distoma holostomum, lludolplii, Sjpiopsis Entoz. 04 & 368, n. 12; 



Dujardin, Hist. Nat. Helminth. 446; Diesing, Syst. Helminth, i. 



339. 

 I I'd/. Intestines of the Spotted Crake, Ortygometra porzana. 



From the collection of M. Siebold. 



