72 SKEXEID.i:. 



upper and under sides ; the ribs become slightly nodulous at 

 the points where they are crossed by the keels, and they seldom 

 extend on either side to the periphery : colour reddish-brown 

 or pale-tawny, the keels being of a bright golden hue : spire 

 not so much sunk below the level of the last whorl as in IT. 

 atomus: apex blunt: ichorh 3. compactly coiled, somewhat 

 compressed, with a slope from the peripheral keel in an equal 

 degree on both sides ; the last whorl is much larger than the 

 next, but not so disproportionately large as in the other species : 

 suture deep : inouth shghtly expanding outwards, with a thin 

 but even edge : it has somewhat of a horseshoe shape, with 

 the rounded end in front, the indentation behind by the peri- 

 phery being considerable : umhilicics wide, open, and nearly 

 flat, completely exposing the interior of the spire: operculum 

 clear-white, rather concave, and having 2 or 3 rapidQy enlar- 

 ging turns. L. 0-0115. B. 0-025. 



Habitat : In rock-pools among seaweed ; a scarce 

 species, although equally diffused with H. atomus. The 

 following list of places where it lias been found may be 

 useful to collectors : — Lerwick, Skye, Bantry Bay, Cork, 

 Scarborough, Sandwich, Isle of AVight, AVeymouth, 

 Falmouth, Tenby, and ^Manorbeer in Pembrokeshire, 

 Oxwich and Caswell Bays near Swansea, and Guernsey 

 (J. G. J.) ; Moray Firth (Gordon) ; '' Landsborough's 

 Bay^^ in Arran, X.B. (Xorman) ; co. Donegal (War- 

 ren) ; Roundstone, co. Galway (Barlee and Alcock) ; 

 Exmouth (Clark) ; Mousehole near Penzance (Templer) ; 

 Land^s End and other parts of Cornwall (Webster) ; Sark 

 (Mrs. Collings) . Its exotic range is less known ; it com- 

 prises a sounding in N. lat. 55° 36', W. long. 54° 33^ 

 at the enormous depth of 1622 f. (WalHch), Bohuslan, 

 in 10 f. (Malm), Gulf of Lyons (Martin), Spezzia 

 (J. G. J.), Sardinia and the Mediterranean shores of 

 Africa (Costa). 



This is the smallest known species of British shells. 

 It is an object 



'• ^Vliere unassisted sight no beauty sees." 



