440 THE VOYAGE OF H.M.S. CHALLENGER. 



except by the dividing line, is unrecognisable from the rest of the shell ; the base is round, 

 produced and oblique. Suture horizontal, deeply and strongly channelled, with a sharp 

 edge below the channel. Mouth rather straight, semicircular. Outer lip sharp, freely 

 curved, a little inverted above and patulous below. Inner lip oblique, direct and flat, 

 a little concave ; its attachment to the body is very short indeed ; it is there somewhat 

 broadly reverted, in the middle it is but slightly so ; below at the pillar-point where the 

 umbilical callus twists out it is again broader. Umbilicus is small but open, being very 

 little covered by the inner lip ; a narrow, sharpish, but small callus, very low placed, 

 comes coiling down very steeply and forms the point of the pillar, and has a rather strong 

 furrow below it, emargiuating the lip edge slightly. H. 0'28 in. B. - 24. Penultimate 

 whorl, height 0-07. Mouth, height 0*2, breadth 0"15. 



I do not know any species of Natica with which to compare this : making allowance for the 

 umbilicus, for the thinner shell, for the lower spire, for the broader form, and for the deeper suture, 

 Natica islandica, 6m., is as like as any. It strangely recalls some of the genus Amphibola, 

 such for instance as Amphibola fragilis, Lam., or Amphibola tenuis, Gray, or Amphibola burmana, 

 Blandford. 



12. Natica insularum, n. sp. (Plate XXVIII. fig. 2). 



Station 192. September 26, 1874. Lat. 5° 49' 15" 8., long. 132° 14' 15" E. Ki 

 Islands, south-west of Papua. 140 fathoms. Blue mud. 



Shell. — Light, globose, umbilicate, with a blunt scalar spire, and a large slightly oblique 



mouth, a polished, finely striated surface of a rich creamy white colour, barred with two 



broad, interrupted, purply chestnut spiral bands. Sculpture : Longitudinals — the whole 



surface is scored with much-curved hair-like lines of growth, which below the suture are 



strongish. Spirals — there are close-set, fine, crimped, flexuous, scratch-like markings, 



with very obsolete small furrows ; below the suture is a broadish, shelving, flat or slightly 



concave shoulder, very obscurely defined by an obsolete angulation ; the lip of the 



umbilicus is formed by a broad, flat, very feeble cord. Colour: a subochraceous or rich 



creamy white, the colour being slightly richer below the suture ; there are two widely 



separated bands of angular, distant, purply chestnut spots. Of these bands the upper, 



composed of much the largest and most distant spots, lies a good way above the periphery ; 



the other, which is a narrower band, lies somewhat more remote below. Epidermis — none 



remaining. Spire short, broad, conical, scalar. Apex small, polished, pale chestnut, barely 



prominent ; it consists of 2^ whorls. Whorls 6 in all, tumid, well-rounded ; the last is 



very large. Suture strongly marked, very slightly channelled. Mouth little oblique ; 



though the pillar is slightly so, somewhat semicircular, open, white within, except for the 



stains of the external bands which shine through the shell. Outer Up (a good deal 



chipped) : it is very slightly flattened above ; below this its curve is very regular throughout. 



