MUREX. 373 



The animal is entirely yellowisli-white. The head is 

 rather broad and snblunate, flanked by subulate tentacula 

 which are thickened by the union of sustentacula for more 

 than half their length, where they bear the dark eyes. 

 The proboscis is rather long, the buccal mass is armed by 

 corneous jaws, and by a tongue, the axile teeth of which 

 are broadly and irregularly quadrate, or rather pentangular, 

 and are armed by three denticles, the central one highest 

 in position. The mantle is rather lax, and slightly scal- 

 loped at the margin ; its siphonal tube is but slightly 

 prolonged beyond the canal of the shell. " There are two 

 branchial plumes of unequal size and length, taking their 

 origin posteriorly on the left, and ascending obliquely to 

 the right ; the smaller plume is on the left of the larger at 

 its upper part, and is itself divided by a furrow" (Clark). 

 The foot is small in proportion to the shell, ovate, round 

 when at rest, scarcely angulated in front, and rounded 

 posteriorly ; it is obscurely grooved along the centre. The 

 operculum is unguiculated, with its apex terminal, and is 

 marked by semicircular lines of growth. 



3Iurex erinaceus ranges from five to as deep as thirty 

 fathoms, and is probably most abundant between twelve 

 and twenty fathoms on a gravelly or stony bottom. It is 

 common in most suitable localities all round England and 

 Ireland, and becomes a little scarcer as we go north. In 

 the Irish sea it is plentiful. Lieut. Thomas remarks that 

 on the east coast he found it in seven fathoms, in the 

 Estuary of the Thames, at the same depths off the Wold 

 and the Dudgeon, but did not take it to the north of these 

 localities. In the Northumberland catalogue it is men- 

 tioned with doubt ; we find it, however, in the Aberdeen 

 catalogue. We have taken it, though not frequently, 

 in the Hebrides. It ranges to the Mediterranean, and 



