OPISTIIOBRANCHIATE MOLLUSCA. 361 



EXPLANATION OF PLATES. 



The figures, with the exception of Plate II., figs. 2, 3, 13, 14, 17, 20, and 21 ; 

 Plate III., figs. 4, 11, 16, 17, and 20; Plate V., figs. 4, 5, 11, 18, 24, and 25; 

 Plate VI., figs. 6, 8, II, 12 and 14, were all drawn with the aid of a camera lucida. 



PLATE I. 



Fig. 1. Herein ceylonica, n. sp., side view of animal, x 9. 



2. 3 teeth from radula, dorso-lateral view, x 470. 



3. tooth from radula, seen from above, x 470. 



4. ,, jaw plate, x 83. 



5. cutting edge of jaw plate, x 340. 



6. Galvma producta, n. sp., median tooth with one of side plates, x 700. 



7. ,, ,, 4 teeth from radula, with side plates, lateral view, x 350. 



8. ,, view of under-side of head. 



9. ,, ,, jaw plate, restoration from crushed specimen, x 55. 



10. LimjuiHii rinemi, n. sp., median and 2 lateral teeth from radula. x 340. 



11. ,, jaw plate, x 16. 



12. lateral tooth from radula, 39th from median, x 340. 



13. ,, ,, 2 outermost teeth from radula. a = outermost, x 340. 



14. I'h iiiiijihi/Ilidia formom, Kel., jaw plate. x8'3. 



15. ,, outer tooth from radula. x 285. 



16. ,, ,, median and 2 lateral teeth from radula. x 285. 



17. Discodoris labifera, Abr., 4 outermost teeth from radula. x 330. 



18. ,, innermost teeth, a = rachis of radula. x 330. 



PLATE II. 



Fig. 1. Plewqphyllidia formosa, Kel., lateral teeth from radula, 8th to 13th from middle, x 136. 



2. Plaiydoris inframaculata (Abr.), under-side, anterior. 



3. ,, ,, branchiae and collar. 



4. teeth from radula, middle of lateral row. x 132. 



5. armature of penis, x 29. 



6. ,, discs from vagina, x 29. 



7. upper part of penis. 



8. Platydoris speciosa (Abr.), lateral teeth from radula, 70th to 74th from middle, x 132. 



9. worn teeth from lateral row of radula. x 1 10. 



10. lateral tooth, side view, x 110. 



11. ,, ,, lower portion of penis, showing armature, x 35. 



12. ,, upper portion of penis, with glans. x 35. 



13. Platydoris In nhniini, n. sp., view of under-side, anterior, x 2. 



14. ,, ,, dorsal view. xl'5. 



15. ,, outermost teeth of radula, 15th and 16th rows, x 370. 



16. ,, ,, penis, upper portion, x 25. 



17. and vagina. 



18. Thordisa (?) caudata, n. sp., innermost teeth of radula. <i = rachis. x 305. 



19. ,, 5 outermost teeth of radula. x 305. 



3 A 



