298 POLLICIPES CORNUCOPIA. 



ovigerous lamellae were not attached to the fraena ; hence 

 I conclude that the fraena are functionless in these three 

 species. 



Affinities. — T have already remarked on the close rela- 

 tionship between this genus and Scalpellum ; there is 

 also some affinity with Lithotrya. 



Distribution. — All over the world. The P. cornucopia ranges from Scot- 

 land to Teneriffe : the P. polymerus is found in opposite hemispheres in the 

 Pacific Ocean, extending from California to at least as far as 32° south of the 

 Equator. 



Geological History. — Having so lately given, in the 

 ' Memoirs of the Palaeontographical Society/ a full ac- 

 count of all the fossil species known, I will not repeat 

 here the conclusions there arrived at. I will only state, 

 that species of Pollicipes are found in all the formations, 

 extending from the Lower Oolite to the Upper Tertiary 

 beds. 



1. Pollicipes cornucopia. PI. VII, fig. 1. 



Pollicipes cornucopia. Leach. Encyclop. Brit. Supp., vol. iii, 



1824. 



— Smythii, var. Leach. Ibid. 



Lepas pollicipes. Gmelin. Systema Naturae, 1789. 



— gallorum. Spengler. Skrivter Naturhist. Selskabet, 



Bd. i, Tab. vi, fig. 9, 1790. 



P. capitulo, valvarum duobus aut pluribus sub-rostro 

 verticillis instructo: valvis albis, aut ylaucis : _pedimculo, 

 squamarum densis verticillis symmetrice dispositis. 



Capitulum with two or more whorls of valves under 

 the rostrum ; valves white or gray ; scales on the peduncle 

 symmetrically arranged in close whorls. 



Maxillae with three tufts of fine bristles, separated by 

 larger spines : segments in the first cirrus less than half 

 the number of those in the sixth cirrus : caudal appendages 

 multi-articulate: filamentary appendages attached to the 

 prosoma. 



