57 215 



Plate I. 



Aplysia immunda, Bgh. 



Fig. 1. Piece of the anterior back. 



— 2. Thorns of the palate. 



— 3. Elements of the mandibles. 



— 4. Median and first (left) lateral plates. 



— 5. Lateral plates. 



— 6. Outer end of a series of plates, a outmost. 



Figs. 2 — 6 with cam. drawn. 350 X 



— 7. Plates of the posterior stomach. 55 X 



— 8. Penis, a M. retractor. 



Aplysiella incerta, Bgh. 



Fig. 9. A papilla of the back. lOOx 



— 10. The shell, from the upper side. 3 /j. 



— 11. The central nervous system. 55 X. aa Ganglia cerebralia, bb Ganglia pleuralia, between the latter 



the two visceral Ganglia, cc Ganglia pedalia, d N. genitalis, e N. osphradialis, f Ganglia buccalia 

 & gastro-oesophagalia. 



— 12. Elements of the mandibles. 



— 13. Thorns of the palate, a a thorn seen from the upper margin. 



— 14. Median part of the rasp, a median plates. 



— 15. The 24th plate from the end of three rows. 



— 16. Outer end of a row of plates, a outmost. 



Figs. 14—16 with Cam. 350 X 



— 17. Thorns from the posterior stomach. 200 X 



— 18. Cones of the glans penis. 350 x 



Aplysiella ? unguifera (Rang) ? 



Fig. 19. Villus of the back. 100 x 



— 20. The shell, from the upper side. 5 /i. 



— 21. Hinder end of the same, from the underside. 



— 22. Elements of the mandibles. 



— 23. Thorns of the palate. 



— 24. Part of the rhachis of the rasp from the upper side, a median plates. 



— 25. Similar from the underside. 



— 26. One of the interior lateral plates, from the side. 



— 27. A plate from the middle of a series, from the side. 



— 28. Outer end of a series of plates, a outmost. 



Figs. 24—20 drawn by Camera. 350 X 



— 29. Plates of the stomach. I00X 



— 30. Cone of the glans penis. 350 X 



