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WHEELER: 
EXPLANATION OF PLATE VIII. 
ani, First sensory nerve. sp. Spermatozoa. 
an, Second sensory nerve. tex. Main trunk of water vascular 
ér. Brain. system. 
coe. Gut. duml. Dorsoventral muscle. 
é. Eye. irnv. Transverse nerve. 
ggi. Glands opening into the vagina. ts. Testicular sacs. 
hy. Uypodermal cells. tsf. Follicular epithelium of testis. 
/nv. Lateral nerve. z. Uterus. 
mi. Longitudinal muscle. uep. Epithelium of the uterus. 
mnv. Marginal nerve. us. Secretion of the uterus. 
ou. Ostium of the uterus vd.. Vas deferens. 
ov. Ovary. vl. Valve-like nodule in the uterine 
ova. Oviduct. duct. 
Doeeenis: vav. Longitudinal nerve. 
ph. Pharynx. vt. Yolk-glands. 
phi. Longitudinal nerve of the phar- wf. Wimperflamme. 
ynx. x. Nucleus of the uterine epithe- 
phr. Ring-nerve of the pharynx. lium. 
sgl. Slime-glands. z. Ciliated membrane. 
Fic. 1. Just hatched Sywcalidium, showing the still separate posterior gut- 
rami. 
Fic. 2. Adult living Sycelidium as seen in reflected light on a dark surface 
(X Io). 
Fic. 3. Nearly adult Syxcelidium viewed as a transparent object, showing the 
disposition of the nervous system, 
Fic. 4. Adult Sycelidium viewed as a transparent object, but slightly dia- 
grammatic, showing the gut, reproductive organs, and water-vascular system. 
Fic. 5. Two egg-capsules of Syxcalidium, showing their method of attachment 
to the gill-lamelle, etc. 
Fic. 6. Fragment of the ciliated membrane, showing its polygonal areolation ; 
from a desiccated specimen. 
Fic. 7. Adult Syncelidium viewed as a transparent object, to show the distri- 
bution of the glands. 
Fic. 8. Portion of a sagittal section through one of the uteri of Syncelidium,. 
showing the duct and external opening. 
Fic. 9. Portion of a transverse section through one of the uteri of Bdelloura 
candida, showing the duct and external opening. 
Fic. to. Transverse section of Syxcelidium through the middle of the body. 
Fic. 11. Fragment of the water-vascular system of a living Syncelidium. 
