136 
MOLLUSCOUS ANIMALS. 
Natica CLAUSA, t. 34. /. 3. & t. 37. /. 6. Brod. & Sow. Zool. Jour. iv. 372. 
Inhab. North Sea, where the shell was discovered by Capt. E. Sabine. 
Natica Borealis, t. 37. /. 2. 
Shell ovate, subglobose, umbilicated, thin, white, smooth, pellucid ; spire conical, half as long as the 
mouth ; whorls rounded ; suture deep. Mouth semicircular ; inner lip rather thickened, slightly reflexed over 
the perforation of the axis. Axis I. 
Inhab. North Sea. Capt. Edw. Sabine. 
Natica globosa of Capt. King, Zool. Jour. v. 344, is very nearly allied to this species, but the spire is 
shorter and the mouth larger, and the umbilicus smaller. 
Natica suturalis. #.37./. 4. 
Shell ovate, subglobose, thin, subimperforated, pale brown, slightly spirally striated; spire conical; 
whorls rounded, with a deep angular canal at the suture. Mouth ovate, elongate, rather extended in front ; 
inner lip white, slightly reflexed over the slight perforation of the axis. Axis II inch. 
Inhab. North Sea. Capt. Sabine and Capt. Beechey. 
Natica pallida, #. 34./. 15.— Brod. & Sow. Zool. Jour. iv. 372. 
Inhab. Icy Cape. 
The back dark, and the apex often eroded like many shells from high latitudes. 
Natica sordida. var. globosa. #. 37./. 5. — Swain. Zool. III. t. 79. 
This species differs greatly in shape : the most elongated variety is figured under the name of 
N. plumbea. Wood. Cat. Sup. t. 8.f.2-, the common state is figured in Swainson’s Zool. Must. t. 79, under 
the name of N. sordida. I have here figured another variety which differs in being much thinner and more 
globular ; it may prove distinct, but as I have only seen a single specimen, I am unwilling to separate it. 
N. melastoma. Swain, t 72. may be also a variety of it. 
Natica mamilla. 
The operculum is horny. 
Natica semisulcata. 
Shell ovate, suborbicular, solid, pellucid, white, smooth; spire short, convex, rather blunt; whorls 
convex, with six or seven narrow regular compressed lines near the suture, and few round the umbilicus ; 
suture compressed; umbilicus simple, rather large and deep. Mouth very oblique. Axis 6; diam. 
6 lines. 
Natica depressa. #.36./. 2. 
Shell subhemispherical, depressed, white, smooth, pellucid ; spire very low, short ; whorls rapidly 
enlarging, last with five spiral bands of small, square chesnut spots, closely concentrically striated behind ; 
umbilicus very large, expanded, with a very broad anterior rib, and deep posterior cavity. Axis § inch. 
Inhab. 
Natica otis. #. 34./. 13. t. 37./. 3. — Brod. & Soiv. Zool. Jour. iv. 372. 
This species has a notch in the inner lip like N. Glaucina and N. conica, an dmost of the species which 
have horny opercula. 
