48 
A REVISION OF THE GENUS FASCIOLA . 
WITH PARTICULAR REFERENCE TO F. GIGANTICA (COBBOLD) 
AND F. NYANZI (LEIPER). 
By HAROLD G. JACKSON, M.Sc., F.Z.S., 
Lecturer on Zoology in the University of Birmingham. 
(With Plate III and 4 Text-figs.) 
The material which is the subject of this paper was obtained from the following 
sources. 
One tube of flukes collected by Dr H. H. Marshall at Bassein and Rangoon, 
British Burmah (referred to below as “ Rangoon specimens”) 1 ; two tubes sent 
by Mr H. E. Hornby at different times from Northern Rhodesia (referred to 
as “Rhodesia specimens,” “1st collection” and “2ndcollection” respectively); 
and two tubes (Nos. 29 and 65) from the Veterinary Pathology Laboratory, 
Nairobi, British East Africa, collected by Mr R. E. Montgomery (the former 
referred to as “Nairobi specimens”) 1 ; in all comprising 40 species. I am very 
much indebted to Dr C. L. Boulenger, F.Z.S., Professor of Zoology at Lahore, 
for entrusting me with the description of this material. 
The tubes contained elongated flukes of the genus Fasciola. It was found 
on examination that all the specimens (with the exception of those contained 
in the tube, Nairobi, No. 65) were related to Fasciola gigantica (Cobb.) and 
the question of the relationship of the various elongated flukes, that have 
been described from time to time under different specific names, with Cobbold’s 
species and these new specimens, was thus raised again. 
The question may be stated thus—do all these forms belong properly to 
F. gigantica (Cobb.) or should they be split up into more than one species? 
The history of the matter can briefly be told 2 . F. gigantica was described by 
Cobbold (1856) from specimens found in a giraffe belonging to a travelling 
menagerie.—Railliet (1895) communicated the discovery of an elongated fluke 
in Senegal cattle, slaughtered at St Louis and provisionally named it 
F. hepatica var. angusta. —Looss (1896) described a fluke from cattle 
slaughtered at Cairo that he named F. hepatica var. aegyptiaca, but which 
he considered a distinct species in 1899.—Blanchard (1896) suggested that 
both these varieties were in reality the same as Cobbold’s F. gigantica but he 
gave no evidence or figures to support this suggestion.—Looss (1902) re¬ 
turned to the subject after examining a large number of specimens from 
1 Received from the Quick Laboratory, Cambridge. 
For detailed discussion of the earlier history and complete bibliography see Stiles 1894-95. 
