44 
tine with pharynx closely following the oral sucker; esophagus moderately long; 
intestinal ceca simple, extending to extreme aboral end of body. Genital pore postero- 
lateral of and in immediate vicinity of ventral acetabulum; it is surrounded by a 
muscular ring {genital ring), the outer free margin of which is provided with a not 
quite complete wreath of beiit chitinous rods with lateral branches. True copulatory 
organs absent; male and female genital tubes unite before reaching the pore, thus 
forming a genital cloaca. Male organs: Testicles oval, in extreme aboral end of body, 
on same transverse plane, their longitudinal axis nearly at right angles to the longi- 
Fig. 68. — Ventral view of Heterophyes heterophyes, enlarged to show the anatomy; ac., acetabulum; 
es., esophagus; ex. p., excretory pore; g. c., cerebral ganglion; gL, glands; g. p., genital pore; 
g. genital ring; i., intestinal ceca; L. c., Laurer’s canal; m., mouth with oral sucker; oo., ootyp; 
ov., ovary; p. b., pharj’ngeal bulb; p. p., prepharynx; p. pr., pars prostatica; r. .s., receptaculum 
seminis; t., testicle; tit, uterus; ra., vagina (metraterm); v. cL, vas deferens; v. p., vitellogene 
glands; v. s., vesicula seminalis; v. t., vitelloduct. (After Looss, 1894, fig. 1.) 
tudinal axis of the body; vesicula seminalis flexed, anterior end of latter forming a 
pars prostatica, both lying free in the parenchyma. Female organs: Ovary globular, 
median, or lateral, anterior of testicles; receptaculum seminis as large as ovary and 
building a sac-like evagination of Laurer’s canal; vitellaria but slightly developed, 
situated on the margins of the posterior division of the body. Uterine coils not 
numerous; they extend laterally nearly to the aboral end, never posterior of the 
testicles, and not anterior of the ventral acetabulum. Fggs not numerous, with 
dark colored thick shell, 20 to 30 /^ by 10 to 17 /n 
Habitat. — Intestine of mammals and birds. 
Type species. — Heterophyes heterophyes (Siebold, 1853) Stiles, 1901. 
