TERTIARY MOLLUSCA. 125 



Turbo antiguensis, new species. 

 (Plate 5, Figures 4 a-c.) 



The following is a description of this species: 



Spire moderately elevated, imperforate; whorla convex, with greatest 

 diameter below the middle of the whorl; suture impressed; surface covered 

 with revolving rows of nodules, about 20 on the body-whorl; on the body- 

 whorl the nodules of the 3 or 4 rows nearest to the suture are elongated 

 obliquely and fused with those of the adjacent rows, producing falsely pro- 

 tractive ribbing; remaining nodular rows alternating in size; secondary sculp- 

 ture of fine revolving threads within the internodular and interfilar spaces on 

 the base, but not crossing the nodes. 



Alt., 23 mm.; diam., 24 mm. 



This species resembles in shape and size Turbo crenorugatus Heilprin 

 from the Tampa "silex" bed, but is differently sculptured; it is probably 

 related to the unngured T. dominicensis Gabb from Santo Domingo. 



Locality. — Rifle Butts, Antigua, station 6854, Vaughan. 



Geologic horizon. — Oligocene. 



Type— U. S. Nat. Mus. No. 167034. 



Turbo species. 

 The following is a partial description of this species: 



One mold of a Turbo with a high spire. The sculpture of the whorls above 

 the carina is indistinct, but several revolving threads are visible. The base 

 of the shell is ornamented with 4 or 5 strong revolving threads between which 

 are several smaller beaded threads. The basal fasciole is rather large and 

 prominent. 



Alt., about 23 mm.; diam., about 20 mm. 



This species is quite distinct from T. antiguensis and T. crenorugatus 

 and appears to be undescribed. 



Locality. — Consolation del Sur, Cuba, station 3474, the Alcalde, 

 collector. 



Geologic horizon. — Oligocene. 



Margarita naticoides, new species. 



(Plate 5, Figures 5 a, 6.) 



The following is a description of this species: 



Shell naticoid, polished, pearly within, smooth except for fine growth-lines; 

 whorls 3$, strongly convex anteriorly, but flattened or slightly concave in 

 front of the suture; suture distinct; spire low; base convex; aperture circular; 

 outer lip attenuated, inner lip incrassated; umbilicus rudimentary. 



Alt., 10.5 mm.; width, 11.4 mm.; length of aperture, 8 mm. 



Locality. — Angela Elrnira asphalt mine, near Bejucal, Cuba, stations 

 3652, 5312, Wiebusch, collector. 

 Geologic horizon. — Oligocene? 

 Type— U. S. Nat. Mus. No. 167028. 



