STROMBUS. 



a short canal in most cases ; very seldom by an elongated 

 narrow canal extended nearly to the point of the spire. 

 The outer lip is sharp edged and entire when young, but 

 becomes more or less expanded and thickened with age, 

 when it forms a simple, entire wing, lobate at its upper 

 edge, very rarely having several small notches both at 

 the upper and lower ends ; but having a distinct, and in 

 most cases very strongly marked sinus near the inferior 

 extremity : in one or two instances this is very indistinct, 

 particularly in the Stroinhus cancellatus of Lamarck. 



These marine shells are found in warm climates, 

 there is a considerable number of recent species, some 

 of which have been lately illustrated by Swainson, and 

 v/e believe there are still several not described by La- 

 marck, though some of those given by Swainson, are 

 evidently published under different names by Lamarck. 

 There are no recent indigenous species in our islands. 



Fossil species are rare, and as far as we know, exist 

 only in the newer formations above the Chalk ; the Lon- 

 don Clay at Barton furnishes one species ; the Calcaire 

 grossiere of Paris another ; a third is found in the con- 

 temporaneous formation at Bordeaux, and two or three 

 in the tertiary Traps of Vicenza. 



Two plates of Strombi are given, of which the first 

 represents three varieties of Str. pugilis. Fig. 1, 2, and 3. 



Fig. 4. Strombus Auris Dianse. 



5. variabilis var, Sw. 



6. . tridentatus. 



7. ^ Fissurella, Linn, cancellatus. Lam. 



8. - ■■ decussatus, DeFr. 



An operculum from a young specimen of Str, gigas, 

 is also given. 



/ 



