A MONOGRAPH OF THE GENUS 



MITRA. 



Char. Gen. Testa marina, spiralis, solicla, turrita, antice 

 caualifera, canali extus tuinulum spiralem effornianti ; labio 

 exteruo plus minnsve incrassato, antice ad canalem einargi- 

 nato ; labio interne- super anfractum ultimum continuo ; 

 columella plicata ; plicis tribus ad sex obliquis. 



Shell marine, spiral, solid, turreted, with a canal in front, 

 the canal forming outwardly a spiral tumulus ; outer lip 

 more or less thickened, anteriorly notched at the canal; 

 inner lip continued on the last whorl; columella plaited, 

 plaits three to six, oblique. 



The sections into which the following species are divided, 

 although not definable, may serve to bring together those 

 most nearly resembling each other. — Species already known 

 are not described in this monograph, and are only remarked 

 upon when necessary to point out such characters and differ- 

 ences as may assist in distinguishing them. New species 

 are described. 



Generally, where the convexity of outline is gradually 

 reduced from end to end, as in If. episcopalis, the term 

 "mitre-shaped" is used; where it is more central, as in 

 "vuljiccitin " group, the term " fusiform." If it is towards the 

 base, we say it is " pyramidal ; " and if towards the spire, 

 "conical." 



