GASTROPODA— RISSOID^E—XENOPHORIDJE. 723 



395. R. decussata Montague. Oligocenic-Recent. 



Moderately high-spired, whorls slightly rounded, sutures 

 slightly impressed ; fine, flat, slightly curved ribs, fine spirals vis- 

 ible only between the ribs, except near the base of body whorl ; 

 anterior notch faint, outer lip moderately thickened, length 7-8 mm. 



Chipolan (Oligocenic) beds of Florida ; Miocenic of France, 

 Italy, and Austria ; Coloosahatchie (Pliocenic) of Florida and 

 Italy ; Recent : Antilles, Mediterranean, Panama, Indo-Pacific 

 region. 



Family Xexophorid.e Desh. 



CXVII. Xenophora Fischer. 

 Broadly conical or trochiform, whorls flat, abruptly angulated ; 

 angulation often prolonged as a sharp, sometimes spinous, rim or 

 carina ; basal portion flat or rounded, surface commonly with 

 agglutinated foreign particles. Cretacic-Recent. 

 .396. X. leprosa (Morton). (Fig. 1052, £.) Cretacic. 



Fig. 1052. Endoptygma umbilicata (left); Xenophora leprosa (right). (After 



Whitfield. ) 



Carina apparently absent, the internal molds appearing rounded 

 at the angle ; embracing of whorls not quite to angle ; surface gen- 

 erally showing cicatrices where foreign particles were attached. 



Ripleyan of New Jersey, Alabama. 



397. X. (Endoptygma) umbilicata (Tuomey). (Fig. 1052, a.) 



Cretacic. 



Smaller than X. leprosa, with open umbilicus and a revolving 

 furrow on basal portion, a third of the distance from umbilicus to 

 periphery. 



Ripleyan of New Jersey, Mississippi, Alabama. 



398. X. conchyliophora (Born.). (Fig. 1053.) 



Oligocenic-Recent. 

 With moderately overhanging carina, emarginate on outer 



