"■'^4 - 



2ype l ocal it: »- Isl&nd in Lake Henri quillo, :5anto l;omincro. 



Hemarks .- This species is not represente^-l in the collec- 

 tions at hanrl. The type is silicifierl and has scni ■■-'*: -re con- 

 sisting of rather riistant more or less lamellar coneentric ru.gae 

 with finer, somewhat irregular intercalated secondary rugae. 

 The single, badly worn fragment from 3ov:den in the i^ational 

 r.-useum collection that has heen referred to this ; ' -s lias no 

 indication of secondary concentric sculpture and the primary 

 rnc-"e are closer and not as lamellose, probahly ''^■^^^ to C'^osion. 

 I'l.e primary concentric rugae are further apart than, on the assoc- 

 iate? P. hrowni n. sp. 



The Tampa siles form is hardly identical with one from 

 Santo Domingo; being smaller with a less prominent posterior 

 dorsal area, more numero^is concentric rugae, without secondary 

 concentric sculpture except near the umbo, v/ith obsolete radial 

 sculpture and finely crenulated inner margins. 



Occiirrence .- Up-ier Oligo^ene: Santo Domingo (&abb, 1''73; 

 Dall, 1905); Lower !:iocene : ?Bov/den he's, Bowden, Jamaica 



(Dall, 1905). 



