- Fig. 1 a, Balanus Ajax; 1 b, scutum external; 1 c, tergum external; and 1 d, scutum, internal view.
- 2 a, 2 b, Balanus stultus, scutum and tergum, external views;
2 c and 2 d, scutum, internal and external views.
- 3 a, Balanus calceolus; 3 b, variety; 3 c, scutum, internal view; 3 d, tergum, internal view; 3 e, spur of tergum toothed.
- 4 a, Balanus galeatus; 4 b, 4 c, scutum and tergum, internal view.
- 5 a, 5 b, Balanus cymbiformis, scutum and tergum, internal view.
- 6 a, Balanus navicula; 6 b, 6 c, scutum and tergum, internal view; 6 d, scutum, external view.
- 7 a, Balanus trigonus; 7 b and 7 c, scutum, external views, two varieties; 7 d, scutum, internal view; 7 e and 7 f, tergum, external views, two varieties.