EXPLANATION OF PLATE XXV. 
Fic. 1.—Atopos sanguinolenta (nat. size): I, male genital 
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aperture ; 2, female genital aperture. 
2.—Ventral view (nat. size): 1, male genital aperture; 2, 
female genital aperture; 3, anus. 
Section of the bodywall, x 460; 1, epidermis, 2, 
unicellular gland; 3, pigment-containing connec- 
tive tissue cell; 4, connective tissue cell (without 
pigment); 5, 6, vertical strands of white fibres; 7, 
muscle-fibre ; 8, subepidermal pigments. 
4,—Head (dorsal’ view), X 4: 1, precephalic flap; 2, 
lower tentacle (left); 3, ommatophore (left); 4, 
opening of the left Simrothian gland. 
5.—Pallial chamber, X 14; 1, ventricle; 2, auricle; 3, 
kidney; 4, aotta; 5, boundary ‘of- the pallial 
chamber ; 6, position of the right lateral border of 
the mantle ; 7, position of the mid-dorsal line (of 
the mantle). 
6.—Portion of alimentary canal, X 2; I, accessory 
digestive gland; 2, digestive gland; 3, wall of 
digestive gland cut open to show the internal 
cavity ; 4, cut end of oesophagus ; 5, oesophagus ; 
6, intestine; 7, vagina. 
7.—Buceal mass, X 2; 1, prtoboscis-sheath; 2, pro- 
boscis ; 3, a portion of oesophagus ; 4, radula-sac. 
8.—Digestive gland of another specimen, X I; I, acces- 
sory digestive gland ; 2, intestine. 
g.—-Longitudinal section through the buccal mass, X 3; 
I, proboscis-sheath ; 2, proboscis; 3, opening of 
oesophagus ; 4, radula-sac; 5, radula. 
10.—Transverse section of oesophagus, X 105. 
a 
, I1.—Portion of radula showing teeth, x 60. 
Jd) 
12.—Two lateral teeth of radula, X 105. 
,, 13.—TIwo median teeth of radula, x 255. 
