MIOCENE MOLLIJSCA AND CRUSTACEA. 89 



The species is a very close neighbor to C. contracta Say, now common 

 on our coast, l)ut is much smaller. When compared with small specimens 

 of that shell it is seen to ])e much heavier, also shorter, with a larger 

 beak, but diflFers princijjally in the surface markings; the concentric ridges 

 being- two to three times as heavy as on any dwarfed or young specimen, 

 of corresponding size, which I have seen among those examined from many 

 localities. The small variety from Beaufort, N. C, approaches it most nearly. 

 They also show radii in the young state, which this does not possess. 



LocaVdji : The specimens are from near Shiloh, N. J., from the greenish 

 gray marls, and belong to the National Museum collections. 



Family SAXICAVir>y^. 



GeiiiLS PANOP^A Menard. 



Panop^a GoLDPrssi. 



PI. XVI, figs. 9-13. 



Panopea Goldfussii Wagner: Jour. Acad. Nat. Sci. Pliila., 1st ser., vol. 8, p. 52, PI. r, 



fig. 3. 

 Panopwa Ooldfussii (Wag.) Meek: f'heck List Miocene Foss., p. 12. 



The following is Wagner's description of this species: "Shell oblong, 

 subovate, ventricose, disks with concentric, unequal, shallow grooves; lines 

 of growth coarse and prominent; anterior extremity slightly gaping; anterior 

 margin rounded, anterior dorsal margin elevated; posterior side narrowed, 

 somewhat produced, not reflected ; jjosterior dorsal margin nearly rectilinear; 

 cardinal teeth obliquely compressed, united at the base by the nymph, short 

 and not very prominent." 



"Allied to Panopea reflexa Say, from which it differs in being propor- 

 tionally more elongated, and without reflected margin, in being nearly- 

 closed anteriorly, and in having a straight dorsal line." 



Mr. Wagner's specimens of this species were from the Meherrin River 

 in North Carolina, but judging from his figures I do not think there can be 

 any specific distinction between them and the New Jersey shells, although 

 there is some slight difference in the proportional dimensions of the parts. 

 In the New Jersey specimens the posterior extremity is proportionally 



