APORRHAIS. 251 



spiral lines or striae : colour pale yellowish- white, sometimes 

 tinged with fleshcolour or reddish-brown : spire elongated ; 

 apex compressed : wliorls 12, convex, all but the last of those 

 near the apex angulated in the middle ; the body- whorl is 

 twisted upwards, and occupies more than live-eighths of the 

 spire ; the first two or thi-ee whorls are tumid, quite smooth, 

 and glossy: suture distinct, deeper between the upper than 

 between the lower whorls : mouth narrow, shaped like a lance- 

 head with the point downwards : outer lip large, white, micro- 

 scopically granulated inside ; it is expanded into a broad flap 

 in front, a triangular and incurved process at the base, and 

 another triangular process at the upper corner of the mouth ; 

 the flap has 3 angular processes, the uppermost being larger 

 than either of the other two, which approximate ; each of these 

 different processes (5 in number) is grooved in the middle, 

 but the smallest process (which is situate next to the base, and 

 is sometimes rudimentary) less distinctly ; the process above 

 the outer lip diverges from the spire, and seldom extends higher 

 than within six whorls from the apex : inner lip spread Hke 

 a white enamel over the under side of the last and penultimate 

 whorls, as well as over the basal process or beak, behind which 

 it is folded so as to make a slight cavity : opercuhun closely 

 laminated, with an obscure and irregular nucleus, faintly stri- 

 ated lengthwise. L. 1-85. B. (to the extreme point of the 

 outer lip) 1*25. 



Yar. albida. Whitish. 



Habitat : Coralline zone (occasionally the deep-sea 

 zone also) on all our coasts. The variety was found by 

 Mr. Waller in Dublin Bay, and by myself in Shetland. 

 This common shell has been recorded from the npper 

 Miocene, Pliocene, and almost every newer tertiary and 

 quaternary deposit in Europe, from the sea-level to 

 1360 feet above it. North Atlantic from Finmark and 

 Iceland to Gibraltar, the Mediterranean, Adriatic, and 

 iEgean, at various depths between 5 and 100 f. 



It is shy, slow, and awkward in its movements, twisting 

 about its long neck and foot in order to gain a creeping 

 posture. Among other fanciful names given to this 

 odd-looking shell are ^' blobber-lipt Edinburgh whilk ^^ 



