102 Description of some New Species of Fossil Shells. 



M. ehurnea. PI. 1, fig. 21. 



M. testa sub-turrita, Igevi, sub-crassa, polita ; spira sub-elevata, 

 acuta ; suturis impressis ; anfractibus octonis, sub-planulatis ; basi 

 striata ; columella triplicata ; apertura sub-ovata. 



Shell sub-turrited, somewhat thick, smooth, polished ; spire 



acute, elevated ; sutures impressed ; whorls , nearly flat ; base 



striated ; columella with three folds ; mouth sub-ovate. 



Length -6. Breadth -25 of an inch. 



Remarks. — In this species the mouth is nearly one third as 

 long as the shell. It much resembles the M. tninima, Lea, but is 

 easily distinguished from that species by its superior size, the 

 three folds on the columella, and. the number of striee at the base, 

 for this species has about twenty very fine ones, while the mini- 

 ma has only four or five large ones. Of the three folds on the 

 columella the lowest one is very small. 



M. elegans. PI. 1, fig. 22. 



M. testa sub-turrita, elongata, sub-crassa, transverse striata, lon- 

 gitudinaliter costata ; spira acuta ; anfractibus septenis, convex- 

 is ; suturis impressis ; columella octophcata, plicis minimis ; aper- 

 tura sub-ovata, angusta. 



Shell sub-turrited, elongated, somewhat thick, transversely 

 striate, longitudinally costate ; spire acute ; whorls seven, convex ; 

 sutures impressed ; columella with eight very small folds ; mouth 

 sub-ovate, narrow. 



Length -5, Breadth -2 of an inch. 



Remarks. — This elegant Mitra has more folds on the columella 

 than any other species I have met with. The M. fenestrata and 

 M. creriulata, with a few others mentioned in Lamarck, having 

 been separated under the name of Conmlix, to which genus, how- 

 ever, this shell cannot be referred, on account of the length of 

 the spire. The longitudinal costse become almost obsolete on the 

 last whorl. The mouth is nearly half as long as the shell, being 

 •2 in length. The last whorl is striated to the base. This shell 

 may be regarded as the link between the genera Mitra and Tere- 

 bra, as it much resembles the T. gracilis, Lea, and T. multipUcata 

 above described ; however, its channel is not either marked or re- 

 curved enough for a Terebra. 



