ABSTRACT
In Pollicipes, at least in certain species, the scuta and terga are articulated together the carina, rostrum, and three pairs of latera, making altogether eight inner valves, are considerably larger than those in the outer whorls the arrangement of the latter, their manner of growth and union are all as in Catophragmus. Considering the whole structure, external and internal, of Catophragmus, with the one great exception of the exterior whorls of valves, there is hardly a single generic character by which it can be separated from Octomeris and Pachylasma. This chapter describes Catophragmus polymerus, and not the Catophragmus imbricatus of Sowerby, in as much as have plenty of excellent specimens of the former, whereas the original specimens of Catophragmus imbricatus. In the British Museum, consist of one old and not perfect shell, without the opercular valves or the included animal's body and the other, though quite perfect, far from mature.
