137 Miocene Fossils, Olsson 17 



which cross each other at right angles ; later whorls about 7, 

 the 1st 4 with only 2 tuberculated spirals, the remainder with 3; 

 the last spiral is introduced above the other 2 and soon equals 

 them in strength ; riblets about 19, straight, extending from 

 the suture across the spirals and their interspaces ; the spirals 

 tuberculat ed by the riblets ; suture distinct, excavated with a 

 small , smooth spiral within ; base markedly flattened, with 2 

 smooth spirals, the uppermost commencing at the suture, the 

 2nd, just below ; the rest of the base is smooth but occasion- 

 ally an obscure spiral is present encircling the columella ; can- 

 al bent to the left. 



Length 4.25, breadth i.jo mm. 

 May be known by its peculiar nucleus, flattened base of 

 last whorl and globose- shape. 



Yorktown formation ; fames river, north of Smithfield, Va.< 



Triphoris bartschi, n. sp., Plate 3, Fig. 7 



Shell sinistral, elongate- conical, with nearly straight sides ; 

 nucleus of about 2 whorls, smooth at first or somewhat spiral- 

 ed, on the next turn with 3 strong, smooth, subequal spirals 

 which later decrease to 2 by the disappearance of the lowermost 

 one ; 9 post -nuclear whorls, with 3 or on the earlier whorls only 

 2 equal, moderately tuberculated spirals ; riblets continuous a- 

 cross the whorl but not onto the base ; the riblets, on the last 

 whorl, number about 21 ; suture well-marked, with a fine smooth 

 spiral ; base flattened, and with 3 (and an indication of a 4th) 

 low, close, smooth spiral ; columella short, truncate and slightly 

 bent both to the right and backwards ; canal open ; mouth large, 

 with the outer lip thin, oblique, expanded below ; anal sinus not 

 evident. 



Length 7.5, breadth 1.J5 mm. 



The spirally sculptured nucleus without riblets, in having the 

 uppermost spiral of the later whorls the weakest and last to 

 appear, will separate this species from its Miocene allies. 



Named for Dr. Paul Bartsch of the United States Nation- 



