294 GENUS — POLLICIPES. 



Valvm ab\& usque ad 100 et amplius: later ibus verticitti 

 inferioris multis; lineis incrementi deorsum ordinatis: sub- 

 rostrum semper adest : pedunculus squamiferus. 



Valves from 18 to above 1 00 in number : latera of the 

 lower whorl numerous, with their lines of growth directed 

 downwards : subrostrum always present : peduncle squa- 

 miferous. 



Hermaphrodite ; filamentary appendages either none, 

 or numerous and seated on the prosoma and at the bases 

 of the first pair of cirri ; labrum bullate ; trophi various ; 

 olfactory orifices generally highly prominent; caudal ap- 

 pendages uni-articulate and spinose, or multi-articulate. 



Attached to fixed, or less commonly to floating objects, in the warmer 

 temperate, and tropical seas. 



It has been remarked, under Scalpellum, how im- 

 perfectly that genus is separated from Pollicipes ; and we 

 have seen under Scalpellum villosum that the addition of 

 a few small valves to the lower whorl, would convert it 

 into a Pollicipes, most closely allied to P. sertus and 

 spinosus. It has also been shown, that the six recent 

 species of Pollicipes might be divided into three genera, 

 of which P. cornucopia, P. elegans, and P. polymerus y 

 would form one thoroughly natural genus, as natural as 

 Lepas and the earlier genera; P. mitella would form a 

 second ; and P. sertus and P. spinosus a third ; but I have 

 acted to the best of my judgment in at present retaining 

 the six species together. As far as the valves of the capi- 

 tulum are concerned, it would be very difficult to separate 

 P. mitella from P. sertus and spinosus. 



as the latter name has been universally adopted throughout Europe and North 

 America, and has been extensively used in geological works, it appears 

 to me to be as useless as hopeless to attempt any change. It may be ob- 

 served that the genus Pollicipes was originally proposed by Sir John Hill 

 ('History of Animals,' vol. iii, 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 Naturgeschichte' for the 

 name Mitella, — a work little known, and displaying entire ignorance regard- 

 ing the Cirripedia. 



