438 THE VOYAGE OF H.M.S. CHALLENGER 



almost quite horizontal. Mouth large, oval, very little oblique, and rather straight, 

 scarcely pointed above ; it is more than two-thirds of the whole height. Outer lip sharp, 

 but strong, patulous throughout. Inner lip straightish, but slightly concave in its whole 

 length ; it is expanded on the labial callus, which is thick, but has no labial nor umbilical 

 pad ; the front of the pillar is thickened and flattened back on the very indistinct circum- 

 umbilical carina. Umbilicus is a rather coarse, pervious, smallish, round hole, hardly 

 encroached on at all by the inner lip ; it is barely funiculate. Operculum membranaceous, 

 thinnish, of a yellow colour, with a dark-maroon outer edge which does not quite coil 

 in to the centre. H. - 27 in. B. 0'25. Penultimate whorl, height '07. Mouth, height 

 0-21, breadth 0-17. 



This species combines a flattened globose form with a prominent pointed base and a small raised 

 scalar spire, in a way that is very peculiar, so much so, indeed, that it almost recalls an Amphibola. 

 Amphibola tenuis, Gray, in particular, has features of resemblance. It very slightly resembles Natica 

 nana, Moller, from Greenland ; but the body-whorl is more depressed, the spire is more exserted, and 

 the umbilicus is not closed, as in that species. 



Professor Hutton, in his revision of the Mollusca of New Zealand (Proc. Linn. Soc. New South 

 Wales, 1884, vol. is. p. 934), which he has kindly sent me, has identified this species with his Natica 

 vitrea. How he has ascertained their identity I do not know, as he has not seen the Challenger 

 specimens, nor even the figures of them, and I dare not flatter myself that the description has been 

 so graphic as to have secured beyond a doubt the recognition of the shells. 



10. Natica atypha, 1 Watson (PI. XXVII. fig. 2). 



Natica atypha, Watson, Prelim. Keport, pt. 7, Journ. Linn. Soc. Lond., voL xv. p. 254. 



Station 188. September 10, 1874. Lat. 9° 59' S., long. 139° 42' E. West of Cape 

 York, south-west of Papua. 28 fathoms. Green mud. 



Shell. — Depressedly conically globose, umbilicate, spire Little exserted, smooth, of a 

 pale faintly ruddyish-white, with an obscure broad rusty band above the periphery. 

 Sculpture : Longitudinals — there are many slight, hair -like, faintly sinuous lines of 

 growth, which towards the suture are gathered into puckerings, and become stronger 

 towards the umbilicus. Spirals — the whole surface is very faintly superficially and 

 unequally furrowed, and is also slightly microscopically and regularly scratched. Within 

 the umbilicus, but finally running out with a twist to the point of the pillar, is an 

 indistinct and blunt circuinunibilical carina. Colour ivory-white, with a faint tinge of 

 buff, hardly glossy ; from the periphery to within one-third of the whole distance to the 

 suture there extends a broad, pale ruddyish-purple band, whose colour deepens on the 

 spire to the apex. Epidermis: none visible. Spire short, the separate whorls being 

 little prominent. Apex rather large and tumid, but depressed. Whorls 4f, the first If 



1 ar-j<f,o:, unpretending. 



