206 



POPULAR CONCHOLOGY. 



semilinear.* — Fossils, resembling Nautilus, but they are 

 not chambered. 



Bucania. Hall. — Shell having the whorls all rolled 

 on the same plane, all visible, and the sides equally 

 convex, the outer one globose, the inner angular, concave 

 below ; the mouth roundish oval, and the inner side some- 

 what compressed by means of the contraction of the next 

 whorl, and the back and sides suddenly expanded. — 

 Fossil. 



PoPtCELLiA. Leveille. — Shell orbicular, very much 

 compressed, almost symmetrical; the spire very distinct, 

 rolled on the same plane, with the exception of the first 

 two or three whorls, which slightly project ; a small but 

 deep furrow on the back separates the whorls into two 

 equal parts, and answers to a small, but pretty long notch 

 in the outer lip ; the umbilicus is very large, showing all 

 the whorls ; the aperture is oval, or almost five-cornered ; 

 the outer lip thin and sharp. — Fossil. 



Family 3. — PHYLLIRRHOA CEA. 



The body entirely naked, compressed, with a tail fin, 

 but no stomach or foot fin ; no gills, and no shell. 



Phyllierhoe. Peron. (Euridice Esch.) — No shell 



Family 4. — SA GITTA CEA. 



The body is spindle-formed, with a tail fin, and several 

 horizontal, or vertical fins, but no gills, and no shell. 



Sagitta Quoy and Gaimard ; Sagitella Lesueur ; Timo- 

 riena and Monophora Quoy and Gaim. ; Pterosoma Lesson. 



* Sowerby's Conckological Manual. 



