57 Olsson, Neocene Fossils 19 



Chione dalli n.sp., Plate 3, Fig's 7-9 



Shell ovate to triangular, slightly convex, very solid ; beaks 

 prominent, approximate, sub-acute ; lunule lanceolate, defined by 

 an impressed line, smooth or with lines of growth ; escutcheon 

 long and narrow, smooth ; surface of shell with thick, flattened, 

 concentric lamellae, fairly regularly arranged on the umbo, later 

 becoming irregular and coalescing towards the basal margin ; no 

 radial sculpture present ; hinge fairly heavy, with three cardinal 

 teeth in each valve ; pallial sinus merely a small notch ; margin 

 minutely crenulated. 



Type. Length 2j, height 20, thickness 6 771m. 

 Larger shell. Lenght 25 , height 21 , thickness 6 mm. 



On page 1290 Dall, in his Tertiary Geology of Florida, vol. 3, 

 pt. 6, briefly describes without naming a Chione from Petersburg 

 Virginia which appears to belong to this species. This species 

 bears some resemblance to C. cortinaria Wagner but may be dis- 

 tinguished by its irregular concentric lamellae and the entire ab- 

 euce of the radial sculpture. At Claremont wharf the species occurs 

 in blue cla3 r s of the St Mary's formation, accompanied by several 

 unusual species. Area virginice Wagner is very common here, and 

 a small triangular Glycymeris like Pechinculns virginice Wagner 

 showing relationship with G. subovata Say, of which it is probably 

 a mutation. 



St Mary" s formation ; James river at Clare7nont wharf ", Va. 

 Phacoides (Pseudomiltha) wongi, n.sp., Plate 1, Fig. 2 



Shell orbicular, thin, inflated, inequilateral ; beaks small and 

 slightly prosogyrate ; lunule very deep and oval, extending un- 

 derneath the beak ; anterior extremity rounded, posterior extrem- 

 ity only slightly rounded, and in the young shell verging on 

 truncation ; dorsal margin straight, slightly angulated at the end; 

 posterior dorsal slope slightly impressed, anterior dorsal portion 

 somewhat wing-like and separated from the rest of the shell sur- 

 face by irregular marks of compression ; basal margin widely 

 rounded ; surface with irregular concentric wrinkles, which on 

 the posterior dorsal slope are more evenly spaced ; in addition, 



