351 



Costa Rica Miocknk — Olsson 



79 



Genus SC0B5WELLA Conrad 



Scobinella Morierei (lyaville) Cossmann 



Plate 4, figures 3, 4 



Euchilodon Morierei Laville, in Cossmann, 1913, Jour, de Conchylio- 

 logie, vol. 61, p. 34, pi. 3, figs 6, 7. 



Shell of medium size, with spire and last whorl of nearly 

 equal lengths; sculpture of numerous, close, bead-like spiral 

 cords, 3 or 4 on the spire-whorls, 18 or more on the last whorl 

 and canal; the sutural fasciole is rather narrow, shallow and 

 concave and with 4 much finer beaded cords; the suture is bor- 

 dered in front by a heavy beaded spiral, which on the early spire- 

 whorls, nearly fills the entire fasciole ; columella with four sharp 

 folds, the largest above; canal nearly straight; aperture narrow, 

 wath a lirated outer lip. 



Length 49, diameter 15, last whorl 33 mm. 

 This is one of the most elegantly sculptured Pleurotomoids 

 in the Gatun beds of Panama and Costa Rica. Described by 

 Laville and Cossmann from Mindi in the Canal Zone, we have in 

 addition collected the species from Toro and Water Cay, (where 

 it is fairly common) , Bocas del Toro and from Limon. The pre- 

 dominating spiral sculpture and columellar folds are very sug- 

 gestive of Mitra. 



Gatun Stage: Mindi, C. Z. (^Laville a7id Cossmann) 

 Toro aud Water Cays, Pa7iama. 

 Bocas del Toro, Pajiama. 

 Port Linion, coral limestones. 



Shell large, thin, buccinoid in form; spire elevated v/itli 

 shouldered whorls and deep sutures; whorls 3 plus, the earlier 

 ones missing; the profile of the whorls is convex with a wide, 

 shouldered, flattened or even slightly concave band just in front 

 of the suture; the surface of the spire- whorls is smooth and un- 

 sculptured but the early ones show very faint spiral bands; the 



Genus HALIA Risso 



HaSia americana, n. sp. 



Plate 4, figure 7 



