PLATE L 
Fig. 1. Limacinci helicina. 
1. Head seen from the right side ; a, right tentacle ; b, fin ; c, tentaculiform lohe of the fin ; d, posterior 
lobe of the foot ; e, columellar muscle ; /, mantle ; g, “ balancer,” or lateral lohe of the mantle ; 
h, genital opening ; i, seminal groove. 
Fig. 2. Limacina lesueuri. 
2. Dorsal view, with the penis (c) evaginated ; a, the head, with two tentacles and the seminal groove ; 
b, “balancer”; c, penis. 
Fig. 3. Limacina helicina. 
3. View from the right side, the mantle, as also the heart and kidney, having been removed from that side ; 
a, fin ; b, posterior lobe of the foot ; c, buccal mass ; d, oesophagus ; e, one of the four large 
stomachal plates ; /, the posterior dorsal azygous plate ; g, intestine ; h, anus ; i, gonad or genital 
gland ; /, genital duct ; Jc, accessory genital glands ; l, seminal groove ; m, columellar muscle ; n, 
pallial cavity ; o, central nervous system. 
Fig. 4. Limacina lesueuri. 
4. The evaginated penis, seen from the right side. 
Fig. 5. Limacina helicina. 
5. Dorsal view; a, “shield” or pallial gland; b, kidney; c, heart, visible owing to the transparency of 
the mantle. 
Fig. 6. Actseon tornatilis. 
6. Dorsal view ; a, b, c, as in fig. 5 ; d, cephalic hood. 
Figs. 7, 8. Limacina helicina. 
7. Central nervous system, seen from the left side; a, buccal mass; b, oesophagus; c, cerebral ganglion; 
d, cerebral commissure ; e, pedal ganglion ; /, right visceral ganglion ; g, left visceral ganglion ; 
h, otocyst; i, tentacular nerve; j, nerve to the fin; 2, 3, visceral nerves; left pallial nerve. 
8. Central nervous system, seen from the ventral side ; a , cerebral ganglion ; b, pedal ganglion ; c, right 
visceral ganglion ; d, left visceral ganglion ; e, otocyst ; /, nerve to the fin ; 1, right pallial nerve ; 
2, 3, visceral nerves ; left pallial nerve. 
Figs. 9-12. Peraclis reticulata. 
9. Dorsal surface of the head; a, head with the tentacles; b, fin; c, posterior lobe of the foot; 
d, operculum. 
10. Pallial gland seen from within. 
11. Distal extremity of the genital duct, seen from the right side; a, genital aperture; b, muciparous 
gland ; e, albuminiparous gland ; d, vesicula semin'alis. * 
12. Central nervous system, seen from the ventral surface ; the cerebral commissure having been divided 
and the cerebral ganglia reflected ventrally ; a, cerebral ganglion ; b, pedal ganglion ; c, right visceral 
ganglion; d, azygous median visceral or abdominal ganglion; e, left visceral ganglion; /, otocyst; 
g, cerebral commissure; b, cephalic nerve; i, nerve to the fin; 1 , right pallial nerve ; 2, 3. visceral 
nerves ; 4, left pallial nerve. 
