DISTOMA LANCEOLATUM. 185 



Dicroccelium lanceolatum, Dujarclin ; Weinland. 

 Fasciola hepatica, Block ; Jordens ; Bosc. 

 F. lanceolata, Rudolplii ; Moquin-Tandon. 

 Planaria latiuscula, Goeze. 



General and Specific Characters. — A small, flat trematode helminth, measurmg rather 

 more than the third of an inch in length, and about one line and a-half in breadth, 

 being also especially characterized by its lanceolate form ; the widest part of the body 

 corresponds with an imaginary line drawn opposite the spot where the blind intestinal 

 tubes terminate, and from this point, on either side, the width of the animal becomes 

 gradually narrowed towards the extremities ; both ends are pointed, but the inferior or 

 caudal one more obtusely than the anterior or oral end ; the general surface is smooth 

 throughout, and unarmed ; the reproductive orifices are placed in the central line imme- 

 diately in front of the ventral sucker, and below the point at which the intestine bifur- 

 cates ; the oral sucker is nearly terminal, and 3^5" in breadth, the ventral acetabulum 

 being about the same diameter ; the testes form two lobed organs placed one in front of 

 the other in the middle line of the body and directly below the ventral sucker ; the 

 uterine canal is remarkably long, forming a series of tolerably regular folds, which occupy 

 the central and hinder parts of the body, reaching almost to the caudal extremity. The 

 vitelligene glands cover a Hmited space, on either side, near the lateral borders of the 

 animal, th.Q for aynen caudale communicates with a contractile vesicle, which passes up- 

 wards in the form of a central trunk vessel, early dividing into two main branches ; these 

 latter reach as far forwards as the oesophageal bulb, opposite which organ they suddenly 

 curve upon themselves, retracing their course for a considerable distance backwards ; 

 the digestive canals are slightly widened towards their lower ends, which occupy a line 

 nearly corresponding with the commencement of the lower fourth of the body ; the ova 

 are conspicaous within the uterine folds, and gradually pass from a dark -brownish colour 

 in front to a pale-yellow colour behind. 



This species, though, comparatively speaking, little known, is 

 by no means of rare occurrence in the sheep and ox. Dujardin 

 constantly met with it in the former of these two ruminants, and 

 he also, in common with Goeze and Bremser, detected it in the 

 pig. Rudolplii observed it in the red deer {Gervus elaphus), and 

 Schaffer in the fallow deer (Gervus dama). It has also been noticed 

 in the rabbit and hare by Zeder and Bremser, and even in the cat 

 (by Eudolphi and Siebold) according to Dujardin ; but, probably, 

 the most common place of abode of this fluke, in the adult con- 

 dition, is the liver of the ox. 



Mehhs was the first to establish the non-identity of this species 

 with the common fluke; a view, which was also shared by 

 Schaffer and Rudolphi, but subsequently abandoned by the latter. 



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