Chthamalus giganteus of Philippi, is the [Pachylasma giganteum] of this work; found recent and fossil.
Chthamalus stellatus, said by Philippi to be found fossil in Sicily; such may be the case, but the littoral habits of the species do not render it very probable.
Balanus carbonarius of Petzholdt, found in the Carboniferous formation! but I have given my reasons, in my ‘Monograph on the Fossil Lepadidæ,’ p. 5, for disbelieving that this is a [Balanus], or even a Cirripede.
Balanus ostrearum appears to be a mere name by Conrad, published by Morton in his ‘Synopsis of the Organic Remains of the Cretaceous Group,’ 1834, Appendix, p. 8.
Balanus peregrinus is briefly described and poorly figured, without the opercular valves, by Morton, in his ‘Synopsis,’ ut supra, p. 72, Pl. 10, fig. 5: this Eocene species apparently resembles the Eocene [B. unguiformis] of Sowerby, described in this work; but quite indispensable details of structure for identification are not given. Another figure of this shell is given in the ‘American Journal of Science’ (N. S.), vol. i, Pl. 2, fig. 6.
Balanus circinnatus, communis, and pustula, of Defrance, as well as all the other species named by him, are described so imperfectly, that the descriptions are of no value whatever, every description being applicable to every species: I must add, that the B. communis is not the B. communis of British authors, a name applied to several forms.
Balanus Finchii is briefly described and figured, but without the opercular valves, by Isaac Lea, in his ‘Contributions to Geology,’ 1833, p. 211, Pl. 6, fig. 222. I do not think that I have seen this species.
Balanus Holgeri, Geinitz, ‘Grundriss der Versteinerungen,’ tab. ix, fig. 19. No opercular valves are given; this species cannot be even approximately recognised.
Balanus proteus, Conrad, ‘Fossil Shells of Miocene Formation of U. States,’ p. 77, Pl. 44 (in ‘Journal Acad. Nat. Sc.,’ Phil., vol. vii, p. 134). I cannot recognise this species; it resembles [B. porcatus]; but as the radii are rather narrow, and apparently with slightly oblique summits, it may be [B. concavus]; the opercular valves are not figured.
Balanus sagittata is merely a provisional name without any description, given in a paper on the Crag by S. Woodward, in the ‘London and Edin. Philosoph. Magazine, Brewster, Taylor, and Phillips,’ vol. vii, July-December, 1835, p. 354.