- 4 71 _ 



Dall (2) resemlDles the less convex iHue, -ji' u i.- liut y. Ic^jl; ex- 

 cavated anterior niarjrin, ribs that are ventrally striated and the 



(2). loc. Git., p. 1205, pi. ^-, fig. 21, 1903. 



point of re'^'xiction of the rihs is r^e-rer the esciitcheon. The 

 Pliocene and recf. .t 2.* laphia (linnae-;j) (5) has a similar appeai"- 



(5). S^'St. Tat., e ■' . 12, p. 1129, 1767; Reeve, 3oBCh. loon., 



vol. li , Teniis . pi. 19, fig. 89, 18 55 (as Vemis -oaphia ) . 



anee, hi^t reaches a larger size, and has a more arcuate oa^e and 

 more closely aopressed rihs. 



Qcenrrence .- Upper Oligocene: Janto T)or.iingo (ua-^o, l''>7"; 

 Guppi, 187^., 1876); lower I'iocene : Bo-.7den he 'S, 3owden, 



."'anaiea (Gnnio;?, 18£6, 1874; Dall, 1905). 



