^53 



Costa Rica Miocene — Olsson 



8i 



Cancellaria dariena var. trachyostraca Brown and Pilsbry, 1911, Proc. 

 Acad, Nat. Sci. Phila., vol. 63, p. 345, pi. 23, figs, i, 2. 



This Species is most abundant in the Canal Zone. It is dis- 

 tinguished from the Barretti Guppy, which it most closely re- 

 sembles by its shorter spire, larger body-whorl and a more irreg- 

 ular spiral sculpture. A large specimen from Mt. Hope, C. Z., 

 has the following dimensions: I^ength 38, diameter 22; last whorl 

 30 mm. Shorter and more globose shells form the varietj^ tra- 

 chyostraca Brown and Pilsbr}^ 



Gatun Stage: Gatun and Mt. Hope, C. Z. 



Water a7id Toro Cays, Panaina, 

 Rio Codes, C. R. 



CanceSlarsa Barretti Guppy Plate 6, figure 6 



Cancellaria Barretti Guppy, 1866, Quart. Jour. Geol. Soc. London, 



vol. 22, p. 289, pi. 17, fig. II. 

 Cancellaria reticulata Gabb, 1873, Trans, Amer. Phil. Soc, vol. 15, p. 



236. In part. 



Cancellaria Bairetti Guppy, 1876, Quart. Jour. Geol. Soc. Ivondon, 



vol. 32, p. 520. 

 Not C. Barretti Maury, which is C. Maiiryce, n. sp. 



This species is the West Indian Miocene analogue or the re- 

 cent Cancellaria reticulata Linne. The most important differ- 

 ence to be noted between the two shells is that in Barretti the 

 columellar plicse are more anteriorly situated and heavier. It 

 is a Miocene fossil in the Bowden beds of Jamaica. 



Gatu7i Stage: Ba7ia7ta River 



Cancellaria Cossmanni, n. sp. Plate 6, figures 9, 11 



Shell of medium size, solid; nucleus of 3, small, smooth 

 whorls; post-nuclear whorls 5, sutures deep; the whorls are 

 slightly channeled or coronated just below the sutures; sculp- 

 ture is evenly but coarsely reticulated by numerous, slightly ob- 

 lique, narrow ribs, crossed by heavy, raised, narrow, .spiral cords; 

 the last whorl show 21 or 22 ribs; the spirals consists of narrow. 



