MOLLIJSCA OP THE ' CHALLENGER ' ESPEDITIOlSr. 343 



but from about one third of the way down they become transversely 

 elongate : they are arranged in rows not quite equal, and which 

 are parted by intervals of fully double the breadth of the dotted 

 rows : towards the point of the base the dots tend to return to 

 the round shape, and the rows of largish dots are parted by rows 

 of minute transversely elongated dots which occur in the inter- 

 vals. Besides these, there are over the whole surface the close- 

 set superficial microscopic spiral lines, which seem to be a cha- 

 racteristic of the genus. Epidermis excessively thin, membra- 

 naceous, and glossy, of a faint straw-colour. Colour ivory-white. 

 Crown oblique. There is a slight indentation or small conical pit 

 almost completely coated with the glaze of the lip : this little pit 

 is encircled by a very slight and blunt keel. Moii^tli irregularly 

 pear-shaped, being somewhat narrowed above and expanded 

 below. Outer Up projects a little angularly behind, and here 

 it is reverted, thickened, and appressed : from the highest 

 point of its rise it sweeps round to the point of the pillar 

 with a very equable curve ; it is very patulous on the base. 

 Inner lip flexuous, being very convex on the body and openly 

 concave on the pillar. A very thin glaze extends from the outer 

 lip above across the body to the pillar, which has a pretty strongly 

 reverted rounded and twisted edge, up which one can just see into 

 the interior of the shell for nearly two turns. H. 1"15. B. 0'78. 

 Greatest breadth of mouth 0"61. 



This is a delicately beautiful shell, curiously intermediate 

 between S. lignarius, L., and S. punctostriatus, Migh., while per- 

 fectly distinct from both. In form it is less like a Bulla than 

 the latter, while the attenuation above is less, and the expansion 

 of the outer lip below is even greater than in the former. Lying 

 on its face, it is broader and is more flattened, and that, too, more 

 obliquely than either. Its puncto-striate spiral sculpture ap- 

 proaches that of >S^. punctostriatus, Migh. 



2. Scaphander niyeus, n. sp. 



St. 214. Eeb. 10,1875. Lat. 4° 33' K., long. 127° 6' E. S.E. of 

 the Philippines. 500 fms. Gloligerina-ooze. Bottom tempe- 

 rature 41°-8. 



Shell. — Thinnish, obliquely oval, slightly narrowed and rounded 

 above, where the outer lip rises on the right like a tooth ; in 

 front it is rounded with a very blunt angulation at the point of 

 the pillar; ivory-white, glossy, striate, but scarcely stippled. 



