PLATE YI. 
A. (in fig. 1) stands for matured ovum. 
A. (in fig. 3) ,, body-cavity. 
A. (in fig. 6) ,, musculus adductor scutorum. 
B. stands for ovum, not fully matured. 
C. (in fig. 1) stands for young ovarian eggs. 
C. (in fig. 10) ,, outer sack of connective tissue. 
c. stands for inner layer of longitudinal muscular fibres. 
D. ,, genital duct. 
cl. (in fig. 1) stands for epithelium of ovarian wall. 
d. (in fig. 3) ,, cement-ducts. 
gl. stands for pancreatic gland. 
GS. or G. supracesophageal ganglia. 
GA. ,, genital aperture. 
L. , , labrum. 
Z. ,, cceca of the so-called liver. 
M. , , mouth. 
O. stands for ovarian coeca. 
oc. „ eye. 
Od. or ov. oviduct. 
Oe. ,, oesophagus. 
0. n. ,, four optic nerves. 
P. , , pancreatic gland. 
p.n. ,, peduncular nerve. 
S. (in figs. 4 and 6) stands for stomach. 
S. (in fig. 10) stands for funnel at the end of the oviduct. 
S', stands for curious sack. 
t. ,, testicular coeca. 
W. ,, body-wall. 
X. (in fig. 2) stands for yolk-elements of egg. 
X. (in figs. 10 and 11) stands for unknown mass. 
1. -III. stands for small optical ganglia. 
Fig. 1. 
Fig. 2. 
Fig. 3. 
Fig. 4. 
Fig. 5. 
Fig. 6. 
Fig. 7. 
Fig. 8. 
Fig. 9. 
Fig. 10. 
Fig. 11. 
Part of one of the coeca of the ovarium of Scalpellum vulgare, Leach ; magnified 
685 diameters. 
Nucleus with nucleolus of a nearly ripe ovarian egg of Scalpellum vulgare , 
Leach; magnified 685 diameters. 
Part of a section of the peduncle of Scalpellum regium (Wyv. Thoms.), Hoek, 
in its lower half ; magnified 33 diameters. Body-cavity, acting as the main 
cement-duct. 
Figs. 4, 5. Pancreatic gland of Scalpellum parallelogramma, Hoek. 
Part of a transverse section through the cephalic part of the body ; magnified 33 
diameters. 
Section of the gland where it has its greatest diameter ; magnified ] 06 
diameters. 
Fig. 6-9. Anatomy of Lepas anatifera, Linne. 
Sagittal section of the body; magnified 1'5 diameters. 
Lateral view of the upper and front part of the stomach, after the muscles ha ve 
been removed ; magnified 8 diameters. 
Frontal view of a part of the stomach with the supracesophageal ganglia ; 
magnified 8 diameters. 
The eye and its innervation ; magnified 58 diameters. 
The apparatus by means of which the oviduct opens in Scalpellum vulgare , 
Leach ; magnified 106 diameters. 
Same apparatus of Lepas hillii, Leach ; magnified 58 diameters. 
