96 



BULLA constricta. 



TAB. CCCCLXIV.— /o^ 2. 



Spec. Char. Subcylindrical, contracted in thef 

 middle; vertex truncated, perforated ; base 

 obscurely stria:ted; aperture linear, ex- 

 panded at the base, 



X HREE times as long as wide ; the superior flattened 

 part of the whorl is not so broad as in the last, the aper- 

 ture is also more linear, except near the base, where it is 

 very wide. 



Sent from Barton, by the Rev; Mr. Bingley. 



BULLA elliptica. 



TAB. CCCCLXIV— ^^. 6. 



Spec Char. Elliptical, elongated, transverse- 

 ly striated ; vertex perforated ; aperture^ 

 widest at the base. 



1 HE form of this Bulla is a very regular ellipsis, the 

 two extremities being equally rounded ; the length is two 

 arid a half times the breadth; the striae are very fine, 

 rather most distant near the base. 



Not unfrequent at Barton, varying from one to three 

 lines ia length. 



