MALACOZOA. GASTEROPODA. PULMOBRANCHIATA. 323 



end marginate ; the uppermost cell little elevated, ob- 

 lique, with a small circular aperture. Legumen, a pod. 



Shell subarcuate, compressed, tapering considerably toward 

 the lower end, which is rounded; of nine slightly convex, 

 more or less oblique, smooth, transparent cells; the upper- 

 most end marginate, being surrounded by an oblique, opaque, 

 white rim, beyond which is a convex, oblique, little elevated 

 cell, having a small rounded aperture, directed toward the 

 concave side of the shell ; the colour hyaline-white. Length 

 a twelfth and a-half, or two-twelfths of an inch, greatest 

 breadth a fourth of the length. 



Found by me, in December, 1842, among shell sand from 

 Cruden Bay, sent by Mr. Alexander Murray. 



It varies as to its curvature and degree of compression. 

 One specimen, having only seven cells, is bent in two direc- 

 tions. 



Nautilus Legumen. Linn. Syst. Nat. 116. Nautilus Legumen. 

 Mont. Test. Brit. Suppl. 82. PL 19. f. 6. Nautilus rectus genicu- 

 lis depressis. Walker, Test. Min. Rar. PL 3. f. 74. Orthocera Le- 

 gumen. Flera. Brit. Anim. 237. Vaginula Legumen. Risso, Eur. 

 Merid. iv. 16. 



To these may be appended the genera Lagenula and Cceca- 

 lium, already described. 



CLASS III. GASTEROPODA. Page 41. 



ORDER I. 

 GASTEROPODA PULMOBRANCHIATA. P. 42, 72. 



FAMILY II. HELICINA. P. 43, 79. 



GENUS 2. ZONITES. ZONE-SNAIL. P. 45, 87. 



10. Zonites pygm&us. Pygmy Zone-Snail. 



Shell depressed, considerably convex above, faintly 

 striate, semitransparent, rather glossy, umber-brown, of 

 four convex whorls, the suture deep, the umbilicus 

 large. Pyymceus, very diminutive. 



