258 INTRODUCTION. 
Fig. V. Genitalia. Same references as Fig. I. 
Fig. VI. Animal with the penis and lower portion of the dart sac. 
Fig. VII. Dental plate. 
Fig. VIII. Genitalia of II. supprcssa, magnified seven diameters. 
Same references as Fig. I. 
Figs. IX. — XI. H. concaya. 
Fig. IX. Digestive apparatus- Same references as Fig. I. PI. 
XI. 
Fig. X. Genitalia. Same references as Fig. VI. PI. IX., except 
11, which is probably a dart sac ; 12. cloaca. 
Fig. XI. Dental plate, much magnified. 
PLATE XIII. 
Fig. I. — III. Succinea. 
Fig. I. Viscera dissected apart. 1. Buccal body; 2. stomach; 3. 
intestine; 4. rectum; 5. anus; G. salivary gland; 7. ducts of do.; 8. 
liver; 9. testicle; 10. epididymis ; 11. accessory gland of do. ; 12. pros- 
tate; 13. penis; 14. ovary; 15. oviduct; 16. genital bladder; 17. 
pulmonary chamber ; 18. heart; 19. renal organ. 
Fig. II. Genitalia. Same references as Fig. VI. PI. IX. 
Fig. III. Dental plate, a. Natural size; b. magnified; 1. mus- 
cle; 2. dental plate; 3. accessory plate. 
Fig. IV. Nerve centres of Helicina orbicii lata, highly magnified. 
1. Supra-oesophageal ganglia; 2. stomato-gastric ganglia; 3. sub- 
a-sophageal gangUa ; 4. auditory vesicles. 
Fig. V. Spermatozoa from the epididymis, very highly magnified. 
PLATE XIV. 
Glandina tkuncata. 
Fig. I. Animal deprived of its shell. 1. Turbinate mass of vis 
cera; 2. anterior third of the buccal body protruded as in eating; 3 
mouth ; 4. generative aperture ; 5. superior tentacles ; 6. inferior ten- 
tacles ; 7. external tentacles. 
Fig. II. Viscera dissected apart. 1. Buccal body ; 2. oesophagus 
2.* exit of do. ; 3. stomach; 4. intestine; a. rectum; 6. anus; 7. Bali 
vary gland; 8. ducts of do- ; 9. liver; 10. hepatic duct; 11. testicle 
12. epididymis; 13. accessory gland of do ; 12*. vas deferens; 14. pros 
tatc; 15. penis; 16. retractor of do. ; 17. ovary; 18. oviduct; 19. genital 
bladder; 20. vagina; 21. cloaca; 22. pulmonary chamber; 23. pul 
