410 PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. [Ap/ril 30, 



iudging from the carapace ; and besides the Irish specimen, ;a group 

 of three hundred, found by Dr. Rankin and Mr. John Yo,ung in a 

 coprolite from the Lower Limestone Shale, near Carluke, are the 

 only known examples, except some doubtful specimens in the 

 Poolvash limestone of the Isle of Man, and a cast in the Permian 

 limestone of Sunderland. There are several other Carboniferous 

 species of Cypridina. G. radiata has been found abundantly in the 

 Coal-measure shales of Glasgow by Mr. John Young, and in the 

 Coal-measures of North Staffordshire by Mr. Molyneux, F.G.S. 

 Its carapace-valves possess a curious and characteristic stellate 

 structure. G. Wrightiana and C. Brady ana are in Mr. J. "Wright's 

 collection from the Carboniferous Limestone of Cork. G. brevi- 

 mentum is one of the most abundant of Carboniferous Cypridina? ; it 

 is somewhat oval, like C.primceva, but has a much greater notch and 

 sinus, and is rather variable in outline. It occurs in the Mountain 

 Limestone of Belgium, Derbyshire, and Ireland, and probably in that 

 of Caldy Island and the Isle of Man. 



G. scoriacea, C. Orossartiana, C. Thomsoniana, C. Eunteriana, 

 and C. Phillipsiana are from the Lower Carboniferous strata of 

 West Scotland ; the last is not rare, and occurs at Cork also. G. 

 pruniformis is both Irish and Belgian, from the same geological 

 horizon as the foregoing. C. oblonga is from the Cork limestone. 



The foregoing Cypridince have oval-oblong valves notched ante- 

 riorly ; an allied group from the Mountain Limestone have ovate 

 valves, more or less deeply notched in front, for which, having no 

 recent analogues, we institute a new genus Cypridinella. These 

 are common in the Mountain Limestone, and present seven species : — 

 Cypridinella Cummingii from the Isle of Man ; G. superciliosa from 

 Cork (Ireland), Settle (Yorkshire), and Bathgate (Linlithgowshixe) ; 

 G. clausa from Cork ; G. Bosqueti, Vise, Belgium ; G< Maccoyiana 

 and C. vomer, Cork ; and G. monitor, Settle and Vise. The last 

 is typical of the peculiarly produced carapace, with antero -ventral 

 prow beneath the retiring sinus, a form which reminds one of the 

 profile of such iron-clad naval "rams" as the "Monitor" and 

 " Merrimac." 



Carapace-valves like those of Cypridina, but impressed with a 

 transverse dorsal or nuchal farrow, characterize the new genus 

 Cypridinella, leading us towards the Gypridella of De Koninek (re- 

 stricted) ; and equally abundant with the foregoing in the Mountain 

 Limestone we have : — (1) Cypridinella clausa, Cork ; (2) C. Burrovii, 

 abundant at Settle, and its variety longnoriensis, locally plentiful 

 at Longnor, in Derbyshire ; (3) C. intermedia, Bathgate ; (4) C. 

 elongata abundant at Vise, and its variety hibemica plentiful at 

 Cork ; (5) G. galea, Cork ; (6) G. vomer, and varr. cultrata and 

 uncinata, Cork ; (7) G. alta, Cork and Vise ; (8) G. Bosqueti, Vise. 



An additional feature, namely a subcentral tubercle, is the basis for 

 another generic division of the numerous Cypridinoid carapaces of the 

 Mountain Limestone ; and amongst this group we have : — (1) Ctpei- 

 della. Edwardsiana {Cypridina, De Koninek, 1841), which [has the 

 general shape of Cypridinella and Cypridellina, but with a very small 



