772 Mollusks. 



whorl, bat is rounded off by a narrow channel, which proceeds circu- 

 larly, to terminate within a short distance of the aperture, offering, in 

 fact, a broad and smooth porcellaneous separate termination to the 

 pillar. 



In colour, N. intricatais much the most beautiful of English turbi- 

 nated shells. The two specimens differ very much in the depth, though 

 not greatly in the distribution of their tints. In the larger, it is far 

 more rich, of a fulvous brown; in the smaller lighter, and of a porcel- 

 laneous yellow. The smaller whorls are, in the larger, somewhat livid, 

 yellow at the separating line ; in the larger, a pale yellow ; and the 

 beauty of the colouring does not begin above the lower half of the se- 

 cond whorl, from which it descends in four regular lines, at nearly 

 uniform distances, to the margin. These lines are in their ground 

 lighter than the other portions of the surface, and their margins are 

 well defined ; they are also portioned out and intersected with some 

 regularity, by arrow-shaped marks, of which those in the two middle 

 are the most regular. The two external lines are the widest, and their 

 arrows broader and more separate, but that which is nearest the sepa- 

 rating line of the whorl is most irregular. The line nearest the umbi- 

 licus (separated from it however by a white space) is, in the smallest 

 specimen, ornamented with regularly formed arrows, but in the larger, 

 one side only of this marking appears. The marks here denominated 

 arrows, are converging lines closing to a point as they descend, and 

 at this part with more of colour ; but there is no middle line : and in 

 the larger specimen their form is much less regular than in the small- 

 er. From the line of separation of the whorls run a considerable num- 

 ber of brown lines, encircling the convexity of the whorls, and uniting 

 the longitudinal lines of arrowy marks, but not actually crossing them 

 so as to break in on their continuity. The comparative number of 

 these encircling lines, as well as their irregularity, is much greater 

 in the larger specimen. 



A close inspection of these shells, in comparison with a small parcel 

 of Naticse, of about the size of small peas — and which, without en- 

 quiry I had believed to be all of the more common species — has im- 

 pressed me with the belief that the N. intricata is not so rare as has 

 been supposed ; for I found several among them distinguished by the 

 regular lines of arrow-shaped marks, and thereby easily separated 

 from others of a paler cast, and with only one line of obscure linear 

 marks near the border of the whorl. On further examination, I find 

 also on these prettily marked specimens that the spire is less elevated 

 and possesses the general form already described as belonging to N. 



