i6o Bulletin 39 33s 



appears in the I^ower Miocene and has continued into the re- 

 cent fauna. 



Gatun Stage: Gatrin {Brozcm and Pilsbry). 



Genus XEWOPHORA Fischer de Waldheim 



Xenophora conchyliophora Eorn 



Tfochzis conchyliophoyiis Born, 1778, Mus. Caes. IncL, p. 333. 

 Tfochus agglutinans Lamarck, Anim. sans Vert., vol. 7, p. 14. 

 Phorus agglutijians Gabb, 1873, Trans. Amer. Phil. vSoc, vol. 15, 

 p. 241. 



Xenophora conchyliophora Dall, 1892, Trans. Wagner Free Inst. Sci., 

 vol. 3, pt. 2, pp. 360-362. 



Xenophora conchyliophora, Maury, 1917, Bull. Amer. Pal. vol. 5, p. 

 297. 



One immature shell was collected from the upper Gatun 

 beds of Old Man Sam Creek. It is one of the few species which 

 has continued pratically unchanged from Upper Cretaceous times 

 to the recent. It is rare as a recent shell along the northern 

 Panama and Costa Rican coast. Gatun Stage. 



Genus PKASIANELLA Lamarck 

 PhasianeHa moifis, n. sp. 



Shell small, solid, ovate with a short, blunt spire and a 

 small narrow umbilicus; whorls about 4, somewhat convex; su- 

 ture distinct; surface smooth and usuallj- showing no features; 

 in some cases, color markings are preserved as brown, wavy 

 blotches of flammules and with very faint suggestions of fine re- 

 volving lines which are so common on recent small PhasianeHa. 

 Height 3.25, diameter 2.75, aperture 1.50 mm. 



The PhasianeHa punctata Gabb from the Miocene of Santo 

 Domingo, has a longer spire and different color markings. It is 

 much more like the recent P. affinis than the Costa Rican mollis. 

 P. mollis is related to P. umbilicata d'Orbigny but differs in its 

 sculpture. 



