327 



Costa Rica Miockne — Olsson 



55 



Shell small, with a high smooth, conic spire of about 12 

 Vv'horls the earlier post-nuclear v. horls are finely nodulated, the 

 succeeding have the sutures carinated and then simple; bod}- 

 whorl with 20 or more strong, beaded, spiral cords; three spiral 

 cords are usually double or incised with a median line, especially 

 on the anterior canal; the beading of the spiral cords is develop- 

 ed best on their posterior portions; interspaces of the cords near- 

 ly as wide as the cords themselves, smooth or with faint, longi- 

 tudinal lines and frequently a small median spiral. 



Length 30, breadth 13 mm. 

 Gatun Stage: Mt. Hope. 



FAMILY TURRITID^ 



Genus TURR3CULA Schumacher 



Section Surcula H. and A. Adams 



Turricula lavinosdes, n. sp. Plate 4, figure 6 



Shell rather large and moderateh' solid; whorls about 12 in 

 number, heavily sculptured with ribs and spiral cords; nucleus 

 of two smooth, slightly bulbous whorls; post-nuclear v/horls in- 

 creasing uniformily in size; concave above, widest below the per- 

 iphery; suture strongly appressed with a spiral cord in front of 

 it; anal fasciole flat or concave, appearing nearly smooth except 

 for about three, small, widely spaced spirals; remainder of 

 whorls strongly sculptured wdth 8 or 12 axial ribs which are 

 lacking from the anal fasciole and from the base of the last 

 whorl; spiral sculpture of 3 or 4 strong cords on the spire- whorls, 

 becoming 10 or more on the last whorl in addition to those of the 

 a.nterior canal; finer, intercalated threads are present between 

 the main spiral cords on the later whorls; the interval between 

 the spirals is finely, longitudinalh^ striated by long growth lines; 

 anterior canal long and nearly straight, slightly calloused along 



