POLLICIPES. 47 
Genus—POLLICIPES. 
Poxticrpes. Leach. Journal de Physique, tom. lxxxv, Julius, 1817.1 
Lepas. Linn. Systema Nature, 1767. 
Anatira. Brugiére. Encyclop. Méthod. (des Vers), 1792. 
Mireuta. Oken. Lehrbuch der Naturgesch., 1815. 
RaMPHIDIONA. Schumacher. Essai d’un Nouveau Syst. &c., 1817 (ante Julium). 
Po1iyLepas. De Blainville. Dict. des Sc. Nat., 1824. 
CapiTuLuUM (secundum Klein). J. #. Gray. Annals of Philos., tom. x, 2d series, 
Aug. 1825. 
Valve ab octodium usque ad centum et amplius. Lateribus verticelli inferioris multis ; 
lineis incrementi deorsim ordinatis. Subrostrum semper adest. Pedunculus squamiferus. 
CHARACTERES VALVARUM IN SPECIEBUS FOSSILIBUS. 
Carina ab apice ad marginem basalem multum dilatata ; apex plerumque liberé pro- 
minens ; parietes a tecto non distincté separati ; linee incrementi parietum parum oblique. 
Scuta plerumque subsolida, convexa, subtrigonalia, margine tergo-laterali plus. minusve 
eminente, sed non angulo in margines duos discreto. 
t. Scuta, aut levia aut linets tenuibus incrementi solim notata. 
A. Scuta, costa ab apice ad centrum marginis basalis non decurrente. 
B. Scuta, costd, nonnunquam subobsoleté, ab apice ad centrum marginis basalis 
decurrente. 
+t. Scuta, aut longitudinaliter aut transverse (i. e. secundum lineas increment) costata. 
Valves from eighteen to above one hundred in number. Latera of the lower whorl 
numerous, with their lines of growth directed downwards. Sub-rostrum always present. 
Peduncle squamiferous. 
CHARACTERS OF THE VALVES IN FOSSIL SPECIES. 
Carina ; widening considerably from the apex, which projects freely, to the basal 
margin; parietes not distinctly separated from the tectum; lines of growth on the 
parietes but little oblique. Scwta generally somewhat massive, convex, sub-trigonal, with 
1 This is one of the rare cases in which, after much deliberation and with the advice of several 
distinguished naturalists, I have departed from the rules of the British Association ; for it will be seen that 
Mitella of Oken, and Ramphidiona of Schumacher, are both prior to Pollicipes of Leach; yet as the latter 
name is universally adopted throughout Europe and North America, and has been extensively used in 
geological works, it has appeared to me to be as useless as hopeless to attempt any change. It may be 
observed that the genus Pollicipes was originally proposed by Sir John Hill (‘ History of Animals,’ vol. iui, 
p- 170), in 1752, but as this was before the discovery of the binomial system, by the Rules it is absolutely 
excluded as of any authority. In my opinion, under all these circumstances, it would be mere pedantry to 
go back to Oken’s ‘ Lehrbuch der Naturgesch.’ for the name Mitella,—a work little known, and displaying 
entire ignorance regarding the Cirripedia. 
