No. 431.] MORTH-AMERICAN INVERTEBRATES. 895 
7",. Testes very small and elongate and in center of 
body; ovary lobate; uterus does not extend to 
end of intestinal coeca 
Anisoceelium Lühe (Fig. 23) (52) 
7. Testes elliptical, in hinder half of body; ovary 
spherical; uterus extends to end of bod 
Anisogaster Lss. (Fig. 24) (49) 
. Intestinal cceca extend to end of body, or nearly so, and 
are of equal length Subfamily V. Echinostomine 
7#,- Mouth surrounded by a single row of spines. 
o,. Oral spines set in a more or less reniform 
ridge and interrupted mid-ventrally 
Echinostoma R. (Fig. 25) (44) 
0,. Oral spines not set in a ridge or interrupted 
ventrally; a number of unusually large 
spines just back of mouth: in crocodiles 
Stephanoprora Odh. (71) 
m,. Mouth surrounded by a double row of spines. 
o, Spines entirely surround mouth; long pre- 
pharynx present: in fish 
Stephanochasmus Lss. (Fig. 26) (44, 48) 
o,. No spines on ventral side of mouth, but a little 
back of this is a group of short spines 
Dihemistephanus Lss. (Fig. 27) (48) 
fî». Neither a ring of spines nor tentacles present at anterior end. 
J, Testes two in number, one behind the other, often obliquely, but 
never in same transverse plane; body usually elongate 
k,. Ovary separated from one or both testes by half the length of 
the body, the space being filled by the uterus; cirrus sac 
. Subfamily IV. Telorchiine 
NY 
= 
t9 
very long: in turtles . 
/,. Both testes at extreme hiid end of body 
Telorchis Lühe (Fig. 28) (50, 10) 
L. One testis at extreme hinder end and one near ovary 
Orchidasmus Lss. (Fig. 29) (44. 45) 
&,. Ovary not widely separated from testes; uterus usually in front 
of ovary. 
4. Excretory vesicle Y-shaped, with very long stem, which winds 
between the testes ; receptaculum seminis large ; no cirrus 
sac: in the liver of mammals, birds, and reptiles 
Subfamily III. Opisthorchiinze 
m,. Yolk glands do not extend forward of acetabulum ; 
uterus confined between intestinal coeca 
Opisthorchis R. BL (Fig. 30) (44) 
ma Yolk glands partly or wholly in front of acetabulum ; 
uterus usually overlapping intestinal coeca. 
