554 



MOLLUSCA 



PHYLUM VI 



tuberculate ; spire exposed or enveloped. Aperture narrow, exteiiding the whole 

 length of the shell, and canaliciilate at each extremity. Inner lip and the inroUed 



oiiter lip generally crennlate. Jura ((7. titonica 

 Stefan i) to Kecent. 



Trivia Gray (Fig. 1001). Like the preceding, 

 but smaller, and sculptured with raised transverse 

 riblets. Anterior Channel not prolonged, wide and 

 slightly reverted. Tertiary and Eecent. 



Erato Kisso (Fig. 1002). Sniall, ovoid or pyri- 

 form, with short conical si)ire. Aperture narrow. 

 Inner lip smooth, except for anterior columellar 

 Canal notch-like, broad. Cretaceous to Recent. 



^ 



Fig. 1001. 



Trivia affinis (Duj.), 

 Miocene ; Pont 

 levoy, Touraine. 



Fig. 1002. 



Erato laevis Don. 

 Miocene ; Nieder- 

 leis, Austria. 



folds ; outer lip denticulate. 



Family 22. Ovulidae Fleming. 



Like the Gypraeidae^ except that the spire is convolute instead of produced and 

 covered, and the marginal teeth 

 of the radula are peculiarly 

 modified. Tertiary and Recent. 



Ovula Brug. Shell ovate 

 or fusiform, the spire completely 

 enveloped. Aperture produced 

 anteriorly and posteriorly as a 

 canal. Inner lip smooth ; the 

 outer reflected, smooth or 

 denticulated. Tertiary and 

 Recent, 



Gisortia Jousseaume (Fig. 

 1003). Large, thick - shelled, 

 ovate, with short convolute 

 spire. Surface typically keeled 

 or coarsely tuberculate. Body 

 whorl with a blunt ridge ; 



aperture anteriorly and posteriorly with a short canal. 

 gigantea (Goldf.). 



Pedicularia Swainson. Sessile on corals. Miocene to Recent. 



Fig. 1003. 



Gisortia tuberculosa Duclos. Lower Eocene (Londinion) ; 

 Ciiise Lamotlie. 



Eocene. G. (Strornbus) 



Family 23. Cassididae Adams. 



Shell thick, inßated, glohularly ovate, sometimes varicose ; spire short, hody whorl 



very large. Aperture narrow, elongate, anteriorly 

 with short canal. Inner lip resting on an exten- 

 sive callus, sometimes granulated or wrinkled. 

 Outer lip more or less thickened. Operculum horny, 

 with marginal nucleus. Marine. Upper Creta- 

 ceous to Recent. 



Galeodea Link {Morio Montf. ; Gassidaria 

 Lam.) (Fig. 1004). Shell ventricose, not varicose. 

 Canal long, twisted, reverted or bent sidewise. 

 Inner lip greatly expanded, outer lip reflected, 

 often crenulate. Columellar border jDÜcate. 

 Upper Cretaceous to Recent ; maximum in 

 Eocene. 



Fig. 1004. 

 Galeodea carinata 

 Lam. Calcaire Gros- 

 sier ; Grignon, near 

 Paris. 



Fig. 100.- 



Galeodea (Sconsia) 

 amhigua (Solander). 

 Oligocene ; Lattorf, 

 near Bernburg. 



