22 
The Common Liver Fluke — FASCIOLA HEPATICA« Linnaeus, 1758 — of Rumi- 
nants, Man, etc. 
[Figs. 19 to 38.] 
Specific diagnosis. — Fasciola: 18 to 51 mm. long, 4 to 13 mm. broad; pale brown 
to slate in color; the anterior 3 to 5 mm. forms a rather thick conical portion which 
is more or less distinctly defined from the broad, flat, leaf-like body of elongate-oval 
form; this latter widens rapidly to the maximum breadth, then decreases gradually 
in width to the posterior end, which is bluntly pointed. Oral sucker about 1 mm. in 
diameter, round, terminal, but inclines ventrad. Ventral acetabulum about 1.6 mm. 
in diameter, situated about 3 to 4 mm. caudad of oral sucker. Skin provided with 
numerous spines placed side by side in alternating rows extending ventrally as far as 
the posterior border of the testicles, but dorsally not so far; smaller on the cephalic 
cone than on the body. Pharynx elongate 0.7 mm. long; esophagus 0.4 mm. broad, 
rarely over 1 to 1.5 times as long as the pharynx, so that the bifurcation of the 
intestine is immediately anterior of the genital pore; intestinal ceca dendritic, some 
branches extending into the cephalic cone, and the posterior end of the ceca extend- 
ing to caudal extremity of worm; lateral branches longer, much more profuse, and 
more numerous than median branches. Genital pore median, about halfway 
between the oral sucker and acetabulum. Male organs: Cirrus fre- 
quently found extruded from pore, and then recurved; cirrus pouch 
present, containing pars prostatica and vesicula seminalis; testicles 
profusely branched, situated for the greater part caudad of the trans- 
verse vitelloduct. Female organs: Vulva at side of cirrus; uterus 
forms a rosette with numerous coils, and is frequently visible to the 
naked eye as a dark-brown spot immediately posterior of the ventral 
acetabulum; ovary branched and anterior of the transverse vitello- 
duct; vitellaria profusely branched and occupy the entire margin of 
the body from the acetabulum to the posterior extremity; they lie 
dorsally as well as ventrally of the intestine, and become broader 
posteriorly. Excretory system highly developed. Fggs (fig. 21) 
oval, 130 to 145 /i long by 70 to 90 /i broad; miracidium (figs. 22-23) 
conical, ciliated, with oral papilla, two cup-shaped eye-spots, and 
rudimentary intestine; metamorphosis (sporocyst, redia, cercaria) 
takes place in small snails of the genus Limnsea {L. truncatul a a.nd others, figs. 34-38); 
cercaria (fig. 23) whitish, owing to excessive development of the capsule glands, 
encysts upon plants. 
Habitat. — Gall ducts, occasionally lungs, or other portions of the body of cattle 
{Bos iaurus), sheep {Ovis aries), swine {Sus scrofa domesfica), and other mammals;, 
rare in man {Homo sapiens). 
Fig. 19. — The 
Common Liver 
Fluke {Fascio- 
la liepatica), 
natural size. 
(After Stiles, 
1898, p. 29, fig. 
^Vernacular names. — English, Common Liver Fluke; German, Ijcheregel, Leher- 
wurrn, Schafegel; Dutch, Botten, Lererworm\ Danish, Faareflynder; Swedish, Lever- 
mask; French, Douve hepatique, fasciola; Italian, biscuola, distoma epatico; Spanish, 
caracolillo. 
Synonyms. — Fasciola hepatica Linnteus, 1758; Planaria latmscula Goeze, 1782; 
Distoma liepaiicum (Linnaeus) Abildgaard (?); Fasciola hurnana Gmelin, 1790; Dis- ! 
torna {Cladocoelium) liepaticum (Linnteus) of Dujardin, 1845; Fasciolaria hepatica j 
(Linnaeus) Anonymous, 1845; Distomum liepaticum (Linnaeus) Diesing, 1850; Distomum I 
{Fasciola) liepaticum Linnaeus of Leuckart, 1863; Cladocaiiuni liepaticum (Linnaeus) 
Stossich, 1892. | 
Bibliography. — For bibliography, see Hassall (1894) and Huber (1894). For 
more technical discussion of this species, see Leuckart (1889, pp. 179-328). 
For a summary of the 32 cases thus far reported for man see Blanchard, 1888a, " 
pp. 589-595; Leuckart, 1889, pp. 313-328, or Moniez, 1896, pp. 103-111. For a gen- j 
eral discussion of this parasite in English, see Stiles, 1898, pp. 29-48. 
