82 R. BULLEN NEWTON on 



DIMENSIONS. 



Height ... ... ... ... ... ... ... 13 millimetres. 



Length ... ... ... ... ... ... ... 18 



Diameter (closed valves) .. 14 



REMARKS. The sculpture of this species is its chief distinguishing feature, 

 the lateral face of the valves possessing two widely divergent costae, of which the 

 anterior is largest, bordered by unequally wide furrows, whereas the terminal 

 regions bear a crowded series of costae, all touching, the anterior preserving a 

 well rounded character, while those in rear are considerably flattened. These are 

 details unknown to me among described forms of Cardita from either Tertiary or 

 recent seas, and hence the present shell is described as a new species. It must 

 also be comparatively rare, as very few valves have been found in the collection. 



OCCURRENCE. Cuttings Nos. 5, 6, u, 12. 

 COLLECTOR. Mr. Kitson. 



Cardita costsenodulosis, sp. nov. 

 PLATE 9, figs. 22-25. 



DESCRIPTION. Shell strong, trigono-cuneiform, closed, inaequilateral, 

 moderately ventricose, length rather more than a quarter the altitude ; anterior 

 region short, excavated, with smooth, small, cordiform lunule surrounded by 

 finely nodulated costae ; posterior end oblique, produced, depresso-convex, 

 elongately and smoothly ribbed, ligament furrow narrow and short ; umbones 

 anterior, approximate ; cardinal area with a thick, central triangular tooth in 

 right valve bordered by an oblique cavity on each side to receive two strong- 

 divergent teeth of the opposite valve of which the anterior is shortest and 

 thickest ; sculpture consisting of 20 elevated, equi-distant, radial costae, 

 alternating at margin with those of the other valve, minutely and closely 

 nodulated at the summits, nodulations absent posteriorly, costae divided by 

 well excavated, broad and concentrically striated furrows ; adductor scars 

 unequal ; margins thick and widely pectinate within. 



DIMENSIONS. 



Young. Adult. 



Height ... ... ... ... 4 ... 14 millimetres. 



Length 5 ... 20 



Diameter (closed valves) ... ... 4 ... 12 



