Var. (5) modestus: upper part of shell white, lower part uniform blueish-gray, opercular valves as in Var. (1). Hab. unknown.
Var. (6) Stutsburi: ([2 d], [2 i], [2 m], [2 n], [2 o],) white, with or without pinkish-purple stripes, which are often confluent, rendering the lower part of the shell of a uniform purplish tint; epidermis persistent: radii very narrow: tergum narrow, spur sharp, varying in form and in exact position; carinal margin sometimes highly protuberant; basal margin on the carinal side of the spur generally, but not invariably, much hollowed out. Hab. West Africa.
Var. (7) obscurus: (Pl. [5], fig. [2 g],) with narrow, approximate, obscure and often almost confluent, slaty, or pale purplish-brown, or dark slate-coloured stripes. Hab. West Indies, Australia, and unknown.
Var. (8) variegatus: with narrow, approximate, dusky, claret-coloured stripes, transversely freckled with white; shell conical; walls very thin: scutum with the adductor ridge small. Hab. New Zealand.
Var. (9) (an. spec.?) cirratus: (fig. [2 b],) shell very pale purplish-brown, with faint, more or less plain longitudinal stripes, transversely freckled with white; walls thin: scuta with the lines of growth beaded: basis, in specimens growing in groups, irregularly cup formed: maxillæ with the inferior corner extremely prominent. Hab. Mouth of Indus, Australia, Philippine Archipelago.
Hab.—Warmer temperate and tropical seas; extremely common; Mediterranean, Smyrna, Sicily, Coast of Portugal; West Coast of Africa, River Gambia, West Indies, Demerara, Natal, Madagascar, Red Sea, Mouth of the Indus, Ceylon, Philippine Archipelago, East Indian Archipelago, Pacific Ocean, east coast of Australia, New Zealand; extremely common on ships’ bottoms; often attached to floating timber, canes, &c.; often associated with [B. tintinnabulum]; attached to pebbles and various shells.
With respect to the nomenclature of this extremely common species, which is widely distributed in all the warmer seas (excepting, as far as I have seen, on the west coast of America), there is some difficulty. I have no doubt that it is the Lepas radiata of Wood (1815), but Bruguière, in 1789, gave this same name to a [Balanus] which he had not seen, but which is figured in Chemnitz, Tab. 59, fig. 842. I should have thought that this also had been the present species, but Spengler, in describing (Skrifter af Naturhist. Selskabet i, B. 1790) this individual specimen, which he calls L. purpurea, states that it is 13 lines in basal diameter; now this is a size which is never acquired by [B. amphitrite]; and the description, habits, and size, would apply equally well to the species which I have called [B. amaryllis]; but when no notice is taken of such points of importance, as whether the walls are permeated by pores, whether the radii are smooth-edged, whether the scuta are striated, it is impossible to identify with any approach to certainty sessile Cirripedes; and the names given ought, in my opinion, to carry little weight with them. With respect to Lamarck’s Balanus radiatus (1818), the synonyms quoted exhibit some great and inextricable confusion. The B. radiatus, again, of Risso, is a fossil and apparently distinct species. There can be no doubt that the present species is the Lepas balanoides of Poli, (and of several authors who have followed him), and equally little doubt that the present species is not the true L. balanoides of Linnæus, which has a membranous basis, and which I have not seen from the Mediterranean. Under these circumstances I have concluded that less confusion would be caused by giving a new name to this species than by taking that of Wood, which ought not to have been used by him, considering Bruguière’s previous adoption of it.
Under the head of [B. tintinnabulum] I have alluded to the great variation of [B. amphitrite], which consists not only in a vast diversity in the colouring and in the general aspect, but likewise in the degree of obliquity of the summits of the radii, in the form of the terga, and slightly in that of the scuta. In order to show that it has not been from indolence that I have put so many forms together, I may state that I had already named and fully described in detail eight of the following forms as species, when I became finally convinced that they were only varieties: it would require at least thirty figures, which I have not the power to give, fully to illustrate the transitional forms. As with [B. tintinnabulum], the deception is wonderfully enhanced by whole groups of specimens from the same locality exactly resembling each other, and sometimes differing from other groups attached to the very same object. If a person were to get together only some fifty or sixty specimens from only half a dozen different localities, he would almost certainly come to the same conclusion, as I at first did, that several of the varieties are true species; but when he gets several hundred specimens from all quarters of the globe, he will find, to his trouble and vexation, that character after character fails and blends away by insensible degrees, and he will be led, as the more prudent course, to include, as I have done, and I hope rightly, all under one specific name. I have experienced more doubt regarding the last variety, cirratus, than on any other, on account of its peculiar colouring, and from the basis being often irregularly cup-formed. Under [B. concavus] I have remarked how closely some of its varieties approach to [B. amphitrite], and it is to this last variety that they approach; almost the only difference being that the scuta in [B. concavus] are longitudinally striated. Yet some of the varieties of the two species are so distinct that it would be puerile to class them together. I will only add, that after studying such varying forms as [B. tintinnabulum] and [amphitrite] it is difficult to avoid, in utter despair, doubting whether there be such a thing as a distinct species, or at least more than half a dozen distinct species, in the whole genus [Balanus].
As with [B. tintinnabulum], I will first give a full description of the more common forms, alluding only to each less frequent variation, and then separately describe briefly the more marked varieties.
General Appearance.—Shape conical, either steep or considerably depressed; sometimes tubular; orifice either nearly entire or deeply toothed, not large, varying from rhomboidal to rounded-trigonal. Surface of shell smooth, never ribbed, generally naked, but occasionally the yellowish epidermis is persistent; in the same individual, I have seen all the lower part of the shell thus covered and the upper part naked, the line of separation being defined. The colour varies much, even sometimes considerably on the same individual; generally white or pale gray, with dull violet-coloured, longitudinal, moderately broad stripes; these stripes are sometimes equidistant, but more usually they are arranged so as to leave broad white spaces; the stripes fade away by endless variations, the edges of the compartments and the carinal end of the shell longest retaining any colour, until we have a uniformly white shell, generally covered with a yellowish epidermis; or the white is longitudinally marked with hyaline lines; this latter variety has a very peculiar aspect, and I did not doubt it was specifically distinct, until, in a number of specimens on a ship from the West Indies, I got the most perfect series, and another scarcely less perfect series from the Mediterranean, graduating into common coloured varieties. Rarely the dull violet or purple stripes become approximate and dark, so that the whole shell is tinted of a brownish slate-colour, occasionally freckled with white. Again, we have another set of very pretty varieties, with a white or very pale pink ground, with either narrow bright pink or broad pinkish-purple stripes. Again, I have seen numerous specimens of a variety, var. Stutsburi, from the west coast of Africa, in which the upper part of the shell is white, and the lower part shaded with pinkish or dark purple approximate stripes, which often become confluent; in one group, the whole shell being thus uniformly coloured, without any vestige of stripes. I have seen another group from an unknown locality, in which the lower part of the shell was uniformly blueish-gray. A variety from Australia has narrow approximate dark claret-coloured stripes, transversely freckled with white. Lastly, in the variety cirratus, the whole shell is very pale purplish-brown, with indistinct longitudinal brownish stripes, transversely freckled with white lines. I considered this as a distinct species, until quite lately finding forms which I could not possibly determine whether to class as B. cirratus or [amphitrite].