A Monograph on the Sub-class Cirripedia · Charles Darwin
PLATE 6.
_Genus_--BALANUS. Fig. 1 _a_, Balanus improvisus; 1 _b_, scutum, internal; 1 _c_, tergum, external view. 2 _a_, Balanus nubilus, scutum, internal view; 2 _b_, tergum, ditto; 2 _c_, tergum, external view. 3 _a_, 3 _b_, Balanus corrugatus, scutum and tergum, internal view. 4 _a_, Balanus porcatus; 4 _b_ and 4 _c_, scutum and tergum, internal views; 4 _d_, tergum external; 4 _e_, basal edge of the parietes of wall of shell. 5 _a_, Balanus patellaris; 5 _b_, scutum, internal; 5 _c_, tergum, external. 6 _a_, Balanus crenatus. 6 _b_, " " smooth _var._ 6 _c_, " " elongated _var._ 6 _d_ and 6 _e_, " scutum and tergum, external views. 6 _f_ and 6 _g_, " " " internal views.
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