IN THE PLIOCENE DEPOSITS. 103 



wrinkles, following the lines of growth, and crossed by wide obso- 

 lete spiral strise ; aperture suborbicular, extremely large ; outer lip 

 thin ; inner lip broadly reflected on the columella, distinctly relieved 

 from the body behind, and with a semilunate broad groove in its 

 centre; length three-eighths and a half ; breadth three-eighths. 



The very broad, grooved, inner lip at once marks it from the Velu- 

 tina communis of Fleming, or Galericulum Icevigatum of Brown's Illus- 

 trations, which we have represented at Fig. 14 for comparison. — B. 



Found at Dalmuir by Mr Smith. 



8. NATICA CLAUSA. 

 Plate I. Fig. J 6. 



Natica glaucinoides, Thomson, Rec. Gen. Sc. i. p. 133. ? 



Shell glossy, with five volutions, those of the spire very slightly 

 produced, somewhat depressed, grooved above, and well defined by 

 the suture ; upper volutions extremely small ; the spire only mea- 

 suring a fifth of the length of the shell ; aperture oblique, semi-ovate, 

 a little flattened on its interior side ; pillar-lip broadly reflected on 

 the columella, behind which is a semi-lunate umbilicus ; callosity 

 rounded and depressed at its base ; outer lip thin ; the whole shell 

 invested with nearly obsolete longitudinally oblique strise, following 

 the directions of the lines of growth ; length three quarters of an 

 inch ; breadth nearly five-eighths. 



Found at Dalmuir by T. Thomson, Esq. 



This is not the Natica glaucinoides of Sowerby's Mineral Concho- 

 logy, vol. i. pi. 5, which we have copied for comparison, fig. 17. It 

 will be seen that it differs from that shell in the spire being much 

 shorter, the internal side of the aperture being flattened ; in being 

 only subumbiculated, in the callosity being totally different in shape, 

 and invariably covering the umbilicus and never toothed ; and in the 

 spire being only a fifth of the length of the shell, whereas Sowerby 

 says that of the N. glaucinoides is three-fourths the length of the 

 shell. The N. glaucinoides has since been found by Mr Smith at Bute 

 and Helensburgh. — B. 



" N. elausa, described by Mr Lyell, on the elevation of the coast of 

 Sweden. The living analogue of this species is still found in the 

 North Sea as far as Spitzbergen ; it also occurs in North America, as 

 on the coast of Newfoundland," &c. — Deshayes. 



GENUS BULBUS,— Brown. 

 Generic Characters.— -Shell very thin, nearly globular ; body very 



