124 NERITA. NERITE. 



vided, and not quite regular in their size ; the smooth or 

 upper termination produced obliquely into a syphon, the 

 other end rounded : length nearly a quarter of an inch. 

 In fine sand, near Dunbar. 



NERITA. NERITE. 



Shell with a single valve, spiral, gibbous, flat* 

 tish beneath : aperture half orbicular ; the pillar- 

 lip transverse, flattish, and truncate, 



A. The lips without teeth. 1 to 10. 



B. The pillar-lip toothed. 11. ; 



1 . Neiita sulcata. Grooved Nerite, Fig. 56, 57. 



Nerita glabrissimus. Brown, Wern. Soc. pi. 24. f. 12. 



Shell somewhat globular, semitransparent, of a blueish- 

 white color : spires four, rather pointed, swollen and well- 

 defined ; the first very large, the others placed somewhat 

 laterally ; all of them marked with rather remote longitu- 

 dinal striae which are very fine and placed a little obliquely : 

 Aperture broad crescent-shaped ; the outer lip very thin ; 

 pillar-lip rather flat, projecting a little in the middle over 

 the perforation which is long and deep, and marked with a 

 few longitudinal lines : diameter the eighth of an inch. 



Two specimens of this shell we found among the sand in 

 Dublin bay. From the foreign specimens in our cabinet 

 they differ in size and color, the latter being clear white, 

 and three-quarters of an inch in diameter : the grooves also 

 of our shell are merely fine striae, and placed at more re- 

 mote distances, v. m. 



2- Nerita glaucina. Livid Nerite. 



Lister, pi. 568. f. 19 Pennant, pi. 90. f. 1 Da Costa, 

 pi. 5. f. 7 Donovan, pi. 20. f. IDorset Cat. pi. 21. f. 7- 



Shell somewhat orbicular, glossy, slightly wrinkled lon 

 gitudinally, of a livid #rey or pale chesnut-brown color, 

 with mostly a chain of deep chesnut-brown zigzag short 

 lines surrounding the junctions of the volutions, and which 

 are disposed in a longitudinal direction : spires six, round- 

 ed and well defined j the first very large and tumid $ the 



others 



