37 



MiTRA paiva. 

 TAB. CCCCXXX.— /^r 1. 



Spec. Char. Ovate fusiform, short, transversely 

 sulcated ; upper edges of the whorls defined, 

 entire ; aperture elongated, lip plaited with- 

 in ; four plaits upon the columella. 

 Only a quarter of an inch long, and one-eighth wide ; 

 the whorls are slighdy convex, and smooth and shining 

 between the sulci ; the upper sulcus is deeper than the 

 others, and so produces a margin to the whorls ; the 

 plaits within the lip reach nearly to the edge which is 

 sharp. 



MiTRA pumila. 



TAB. CCCCXXX.~Jig. 2. 



Spec. Char. Ovate fusiform, short, trans- 

 versely sulcated ; upper edges of the whorls 

 defined, crenated ; sulci decussated by 

 longitudinal costae ; aperture elongated ; lip 

 plaited within;fourplaitsupon the columella. 



In every thing excepting the longitudinal costaj, this 

 agrees exactly with the last : these costse are numerous, 

 not much elevated, and slightly curved ; they divide 

 the sulci into regular square cells, and give a rough 

 aspect to the shell. 



Many specimens of both the above Mitres have come 

 to our hands through various channels from Barton 

 Cliff. Amongst them we do not find any intermediate 

 varieties. 



