The Sexual Phases of Myzostoma. 
299 
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Wiss. Z. 31. Bd. 1878 pag. 81—100 Taf. 6, 7. 
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Morph. Boston Vol. 6 1892 pag. 481 — 493. 
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Theorie der Vererbung. Jena 1885. 
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Explanation of the Plates 10 — 12. 
Eeference Leiters. 
ac.n nuclei of accessory cells. 
ac. o oral sucker. 
ae.v ventral sucker. 
am parasitic Amoeba. 
an anus. 
c food-particles. 
cl cloaca. 
coe coelom (body-cavity). 
er cirrus. 
ex.p excretory pore. 
/ fissures in the ovary. 
gd gonad. 
gr deeply staining granules. 
int intestine. 
int.ep intestinal epithelium. 
intr intestinal ramification. 
juv young Myzostome. 
U lateral edges of the body. 
mm manubrium. 
ms muscles. 
neph nephridium. 
n. gl nuclei of gland-like cells. 
n.n Zone of small nuclei. 
no ventral ganglion. 
cavity. 
oog oogonia dividiiig. 
o. ut orifice of the uterus. 
ov ovary. 
ov.a anterior ovary. 
ovp posterior ovary. 
p parapodium. 
par parenchyma. 
pen penis. 
p. ep peritoneal epithelium. 
pg pigment. 
ph pharynx. 
pst boss of the segmental sac of M. 
mental sac. 
sep septum. 
s.m smooth muscle cells. 
tral sucker oiDistoma myzostomatis. 
r ring enclosing the boss of the seg- 
o ovum. 
o.a ovum just attached Jo peritoneal 
epithelium. 
o.m ovum migrating through the body- 
platypus. 
g pharyngeal tissue drawn into the ven- 
