I20 



Bulletin 39 



292 



with about 17 on the last v/horl and the canal; aperture suboval, 

 with a heavy but not thickened outer lip, internally lirated. 

 Length 27, diameter 11, last whorl 17, spire 4.5 mm. 



This shell is related to the Phos elegans Guppy of the Mio- 

 cene of Jamaica and Santo Domingo. Our shells differ from 

 typical examples of elegans from Santo Domingo, in being larg- 

 er, and more coarsely sculptured. 



Varix-like thickenings occur scattered along the spire-whorls. 

 The protoconch of typical elegans and limonensis are practically 

 identical. The recent West Coast Phos Veraquensis Hinds is a 

 related but more finely sculptured species. 



Gatun Stage: Port Linion. 



Bocas del Toro. 



Phos estreilensis, n. sp. Plate 9, figures 17, 18 



Shell small, slender, solid; spire much longer than the ap- 

 erture, pointed; whorls of the spire 6 or more, convex in profile 

 with deep sutures; sculpture of narrow, straight ribs which com- 

 mence on the columellar area and pass across the whorl to the up- 

 per suture; there are 12 or 13 ribs on the last whorl which are 

 evenly and widely spaced except on the back of the outer lip 

 where they are smaller and more numerous; the spirals consist 

 of a primary set of threads or cords with a single, smaller second- 

 ary thread in each interspace except on the base and the canal; 

 the primary threads crossing the ribs form small, whitish tuber- 

 cles; the spire- whorls have 4 primary spirals and there are 1 1 on 

 the last whorl, exclusively of the canal; aperture sub-elliptical, 

 produced anteriorly to form the straight anterior canal; outer lip 

 thickened and internally lirated. 



Height 20, diameter 8, aperture 9 mm. 



A small, slender species, coarsely sculptured like the larger 

 and broader Phos Moorei variety costaricensis. It is limited in 

 our collections to the Gatun beds of the Estrella River. 



Gatnu Stage: Coll. 6, 7, Estrella River. 



