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



Sliell. — Strongish, conically globose, slightly pointed below at the base of the mouth, 

 glossy, bright yellow, but whitish around the umbilicus, which is a mere cleft. Sculpture : 

 Longitudinals — there are very slight, rather unequal, hair-like lines of growth. Spirals — 

 the surface is covered as usual with extremely faint superficial wavy lines and furrows, 

 besides which is a system of still more superficial microscopic sharp straight scratches, 

 which it is very difficult to see at all. Colour pure porcellanous white under the brilliant 

 yellow epidermis, which is very thin, glossy, and rather persistent. Sjiire high, but blunt 

 at the top, which is somewhat eroded. Apex large, bluntly rounded. Whorls 4, the first 

 one is large, and the shell increases very regularly ; they are tumid and regularly rounded, 

 and rise high above the succeeding ones ; there is a slight and narrow swelling below the 

 suture, with a very slight and shallow compression of the shell below this swelling. Suture 

 channelled, but not broadly nor deeply so ; it is considerably and increasingly oblique. 

 Mouth large, open, broadly oval, with a slight flattening of its curve on the left side ; its 

 upper corner is very accurately rectangular. Outer lip open but not very patulous, and is 

 a most regular curve in its whole sweep, which passes almost without change into the curve 

 of the pillar. Inner lip is very slightly concave, till towards the front of the pillar it 

 curves round to the right to meet the outer lip ; a very slight pad fills up the upper edge 

 of the mouth, a very thin transparent and straight-edged callus carries it across the body ; 

 over the umbilicus it is slightly thickened and a good deal reverted ; at the point of the 

 pillar, where it becomes adherent, it is encroached on very slightly by a small furrow, 

 which runs out of the umbilicus parallel to the pillar ; below this point the lip has a 

 narrow, rounded, and expanded edge. H. - 54 in. B. 0"47. Penultimate whorl, height 

 0-23. Mouth, height 0"42, breadth 0"3. 



This Paludina-Yike form resembles no Natica known to me. It is intermediate between Natica 

 ajjinis, Gm., and Natica gronlandica, Beck, but is narrower, longer in the last whorl, and higher in 

 the spire than the most exceptional forms of Natica affinis, Gm., var. clausa, Brod. and Sow. 

 Philippi, in Raster's Conch. Cab., reproduces (pi. vii. fig. 1) Natica limlata, d'Orb., Patagonia, 

 and (pi. vii. fig. 2) Natica isdbclleana, d'Orb., from South America, which vaguely have somewhat 

 of the same features, and his Natica tenuis, pi. xiv. fig. 3, has such too : but these are species I do 

 not remember to have seen, and none of the descriptions apply. 



18. Natica fartilis, Watson (PI. XXVII. fig. 10). 



Natica fartilis, Watson, Prelim. Report, pt. 7, Journ. Liun. Soc. Lond., voL xv. p. 264. 



Station 145. December 27, 1873. Lat. 46° 43' S., long. 38° 4' 30" E. Between 

 Marion Island and Prince Edward Island. 50 to 140 fathoms. Volcanic sand. 



Station 149c. January 19, 1874. Lat. 49° 32' S., long. 70° E. Balfour Bay, Eoyal 

 Sound, Kerguelen. 60 fathoms. Volcanic mud. 



Station 150. February 2, 1874. Lat. 52° 4' S., long. 71? 22' E. Between Kerguelen 

 and Heard Island. 150 fathoms. Coarse gravel. Bottom temperature 35°'2. 



