70 
trates. The canal is lined by a columnar epithelium and filled 
by a cuticular secretion of sieve-like appearance. 
cb. the internal cavity in the midst of this secretion. 
Fig. 33. The cuticular secretion inside the last-mentioned organ more highly 
magnified. 
c. the tubular lacunae left free inside the cuticular secretion ch. 
bt. the fine threads appearing to be led outwards along these 
lacunae, originating from the ephithelial cells at the bottom 
probably comparable with a byssus-like secretion. 
Fig. 34. A transverse section as in Fig. 32, but more posterior. 
Rec. the rectum with the ciliated epithelium. 
spm. stronger development of musenlar tissue in its walls forming 
a sort of sphincter. 
(). the posterior unpaired portion of the ducts RR’ (fig. 46). 
m. transverse muscles between the foot and the canal Q@. 
T. the hindermost portion of the ventral furrow with the ci- 
liated folds. 
bb’. the terminal portion (superficially situated) of the sievelike 
euticular contents of the organ Mb Mb’ (fig. 32). 
Fig. 35. The corresponding organ in Neomenia (drawn after one of Prof v. 
GRAFF's preparations), situated in one of the hindermost transverse 
sections. 
I. the integument. 
ic. the internal cavity of the organ corresponding with the exterior. 
ep. epithelial cells formiag a thick lining and on all sides en- 
closing 
b. the cuticular contents. 
Fig. 36—39. Four diagrammatie transverse sections through different regions 
of the body: $ 
Fig. 36. through the mouth and pharynx; Fig. 37. through the 
trunk; Fig. 38. at the spot where the hermaphrodite gland pas- 
ses into the genital ducts (along the line zu in fig. 46); Fig. 39. 
through the rectum, the heart and the genital ducts (along the 
line vw in fig. 46). 
OÖ. mouth. 
P. pharynx. 
t. lip-like fold (cf. fig. 17). 
f. accessory inferior folds. 
c. anterior coecum of the intestine running forwards over the 
pharynx. 
u 
