106 KELLIAD^. 



wavy concentric raised striulae decussate the preceding, 

 but demand, in many specimens, the most searching scru- 

 tiny for their detection. The entire base of the shell is 

 really gaping ; that is to say, when the dorsal margins 

 touch throughout, the ventral edges do not touch at all. 

 This hiation is contracted in the middle, and pointed at 

 each extremity, the former being caused by a shallow and 

 rather broad depression, which is evident near the lower 

 margin, just under the beaks. These latter are minute 

 and by no means prominent, but easily discernible on 

 account of their acuteness. The somewhat tapering ex- 

 tremities of both the sides, which are nearly equal, are 

 tolerably rounded. The dorsal edge is typically recti- 

 linear, and not sloping on either side, the rounding of the 

 extremities being effected by the anterior and posterior 

 margins ; sometimes, however, it is very slightly convex 

 and a little declining on either side ; the ventral is re- 

 fuse in the middle, but convex towards each extremity. 

 There is no distinct umbonal ridge ; the interior is white, 

 and the cartilage pits, which lie under the beaks in the 

 narrow hinge-margin, are extremely small, and somewhat 

 triangularly linear : the hinge is destitute of teeth. 



The animal of Galeomma Turtoni has been described and 

 figured by M. Mittre from life, and some elaborate repre- 

 sentations of it are given by M. Deshayes in his " Mol- 

 lusques d'Algerie." In 1835, it was met with by Mr. 

 Clark at Exmouth, and ample notes and sketches taken, 

 but not published. We have collated these with the ac- 

 count published in the " Annales des Sciences Naturelles," 

 for March, 1847, by M. Mittre, and thus drawn up the 

 following description, never having been so fortunate as to 

 have had an opportunity of examining and delineating this 

 rare Mollusk in a living state. 



