PLATE XXIII 
Fig. 1—3. Balanus navicula Darwin. 
Fig. 1. a@ and 6, scutum and tergum, internal view; magnified 42,5 diameters. 
¢ and d, scutum and tergum, external view; magnified 42,5 diameters. 
Fig. 2. Labrum, with right-hand palpus; magnified 144 diameters. 
Fig. 3. Maxilla; magnified 144 diameters. 
Fig. 4—11. Balanus investitus n. sp. 
Fig. 4. Animal seen from above, attached to an Acanthogorgia, which also covers the Balanus; 
magnified 9 diameters. 
5. Shell, lateral view; magnified 9 diameters. 
Fig. 6. a@ and 6, scutum and tergum, internal view; magnified 10 diameters. 
c and d, scutum and tergum, external view; magnified 10 diameters. 
7. Labrum, with right-hand palpus; magnified 144 diameters. : 
Fig. 8. Mandible; magnified 144 diameters. 
9g. Maxilla; magnified 144 diameters. 
Fig. ro. Outer maxillae; magnified 144 diameters. 
Fig. 11. Sixth cirrus, one of the middle segments; magnified 64 diameters. 
Fig. 12—16. Balanus cornutus n. sp. 
Fig. 12. Shell seen from above; magnified 8 diameters. 
Fig. 13. Shell, lateral view; magnified 8 diameters. 
g. 14. @ and 4, scutum and tergum, internal view; magnified 10 diameters. 
c and d, scutum and tergum, external view; magnified 10 diameters. 
Fig. 15. Third cirrus, longer ramus, 4th segment; magnified 206,5 diameters. 
Fig. 16. Sixth cirrus, eigth segment; magnified 64 diameters. 
Fig. 17—21. Balanus proripiens n. sp. 
Fig. 17. Animal, lateral view; magnified 4 diameters. 
Fig. 18. a@ and 4, scutum and tergum, internal view; magnified 10 diameters. 
c and d, scutum and tergum, external view; magnified 10 diameters. 
Fig. 19. Labrum, with right-hand palpus; magnified 64 diameters. 
Fig. 20. Mandible; magnified 64 diameters. 
Fig. 21. Maxilla; magnified 64 diameters. 
Fig. 21°. Edge of the maxilla, with spines; magnified 206,5 diameters. 
