(sect, c), balanus amphitrite. 241 



the shell of a uniform purplish tint ; epidermis persistent : radii very 

 narrow : tergum narrow, spur sharp, varying in form and in exact 

 position ; carina! margin sometimes highly protuberant ; basal margin 

 on the carinal side of the spur generally, but not invariably, much hol- 

 lowed out. Hab. West Africa. 



•Var. (7) obscurus : (PI. 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 : maxillce 

 with the inferior corner extremely prominent. Hab. Mouth of Indus, 

 Australia, Philippine Archipelago. 



Hab. — Warmer temperate and tropical seas ; extremely common ; Mediterra- 

 nean, 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. tintimiahulum ; 

 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 

 Bruguiere, 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. amarijllis ; but when no notice is taken of 

 such points of importance, as whether the walls are per- 

 meated 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 



16 



