228 



Turt.D.p. 117. With five smooth whorls, parti- 

 tions slightly depressed externally, clear white, pearly 

 within. Diameter of the coil, f . Aberdeen, Kerry, 

 Belfast, Clare 



GENUS. SPIROLINA. 



Multilocular ; the last whorl or two spiral and discoid; 

 volutions contiguous, the last one terminating in a 

 straight line : septa straight, perforated by a 

 tube. 



S. SUBARCUATULA P.p. 277. NAUTILUS S. Mont. 

 Sup.p.SO. t. 19. f. l.Walk. f. 73.Turt. D. p. 

 121. White, glossy, semi-transparent, with 12 joints 

 the first four or five nearly straight and separated by 

 ohlique raised and more opaque lines ; the rest curling 

 spirally inwards and divided by radiating lines ; the 

 back margin furnished with a raised edge and slightly 

 indented by the division of the joints, the front margin 

 obtusely rounded ; aperture oblique with a small syphon 

 at the upper point. I In fine sand. 



S. SEMILITUA. F. p. 227. NAUTILUS. 8. Lin. 

 1 163. Mont. p. 196. D. p. 346. TV*. D. p, 12 1 . 

 Lin. T.S.p. 118. Mart.f. 186. Opaque brown, 

 elongated, subarcuated, chambers diminishing in size to 

 the mouth, which is contracted, outer margin rounded, 



