Cretaceous and Ttrliary Cirripides. 171 



18-'>1. rolUcipes riijidus, J . de C. yowerhy ; C. R. Darwiu, Pal. Soc 

 Muiio^rr. Foss. J.t'jmditliP, p. 7."i, pi. iv. fig. 7. 



18")4. J'u/lici/)cs ii'j/ulus, J. dv C Sowurby ; ('. II. Darwin, Ray Soc. 

 Moiiogr. Subclass Cirripedia, B.ilauidae, Synop. et ludex Systeuiaticus, 

 p. Cy.]S. 



]8o4. Pollicipes vigidus, J. do C. Sowerby ; J. Morris, Cat. Brit. Foss. 

 2iid ed. p. 9(3. 



18(jo. Potlici/ies ritjidus, J. de C. Sowerby ; J. W. S ilter and II. Wood- 

 ward, Cat. and Uliart Toss. Crustacea, p. 27, pi. i. tig. 5. 



1S77. Pollui/ies ri(/idiis, J. de C. Sowerby ; II. Woodward, Brit. Mas. 

 Cat. Brit. Foss. Crustacea, p. 14'J. 



Diagnosis. (!)apitular valves transversely ridged and gene- 

 rally longitudinally ridged. Scuta elongately trianguhii-, 

 with the Ijasi-lateral portion produced and a narrow wall- 

 sided ridge curving from the ajjcx to the hasi-lateral angU;. 

 Tcrga with the apical portion much curved towards the 

 scuta, and a ridge like that of the scuta curving from the 

 apex to the basal angle. Peduncular plates with an inwardly 

 })rojecting ba^al ledge, the inner extremity of which is 

 I'uraished with a median socket; externally these plates are 

 irregularly ridged longitudinally and transversely. 



Distribution. Albian, Gault : Folkestone and ^Maidstone, 

 Kent; Eastwcare Bay, Sussex; Eclaron (Haute-Marne), 

 France. Ceuoniauian, Cambridge Greensaud, near Cam- 

 bridge. Chalk ^larl^ near Cambridge. 



Type. J. de C. Sowerby founded this species on a scutum 

 and two imperfect carinre from the Gault of Folkestone^ but 

 I do not know what has become of the specimens. I select 

 the scutum as the holotype of the species. Of the three 

 valves figured by Darwin (1851) from the Gault of Folke- 

 stone, two, the carina and scutum, are in the Geological 

 Department of the British Museum, registered respectively 

 I. 13043 and I. 13614.. 



Material. Pollicipes riyidus has hitherto been recorded 

 only from the Gault (All)ian), at which horizon it is compa- 

 ratively common, especially at Folkestone. There is in the 

 Geological Department of the British Museum, re<nstered 

 1. 13G70, a single scutum from the Gault of Eclaron (Haute- 

 ^larne), France ; and I have two earinse from the Cainbrid"-e 

 Grcensand, as well as some valves from the Chalk ^lail 

 (Cenomanianj of Cambridge. 



Up to the present only the scutum, tergum, and carina 

 have been described, but we are now able to add considerably 

 to our knowledge of the species by the discovery in the 

 Gault of Folkestone of a rostrum, an upper latus, and 15 

 plates of tlie peduncle. A single upper latus (PI. \l{. fig. 17) 



