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



of the pillar, straight, rounded, and very much expanded on the pillar, with an angulated 

 and very patulous junction to the outer lip in front : there is a small umbilical furrow and 

 chink half hidden behind it. L. 0-082 in. B. 0-08. Mouth, length 0-049, breadth 0-048. 



This species extremely resembles Scissurella eximia, Seg. (see Form. Terz., p. 272, pi. xvi. fig. 

 32), both in form and sculpture, but the base is more tumid, the whole shell more compressed, 

 and the apex is a little larger and more exserted. In its strong radiating ribs it is like Scissurella 

 staminea, A. Ad., from Japan, but is much larger and higher. 



3. Scissurella aedo7iia, 1 n. sp. (PL VIII. fig. 3). 



Station 122. September 10, 1873. Lat. 9° 5' S., long. 34" 50' W. Off Pernambuco. 

 350 fathoms. Red mud. 



Station 135c. October 17, 1873. Lat. 37° 25' 30" S., long. 12° 28' 30" W. 

 Nightingale Island, Tristan da Cunha. 100 to 150 fathoms. 



Shell. — Depressedly globose, strongly sculptured, with a rather high scalar spire, 

 exserted whorls, a very sharp and expressed carina, a minute tabulated apex, a strong and 

 impressed suture, a tumid base, and a large pervious but half-covered umbilicus. Sculp- 

 ture : the radiating ribs are pretty strong, sharp, and equal above and below the canal. 

 Spirals — the whole surface is closely, sharply, and regularly scored with fine threads, 

 which are a little stronger (but not quite so sharp) on the base than above. Colour 

 white. Spire high, scalar, each whorl rising and expanding above the suture. Apex very 

 small and tabulated. Whorls 5 ; they slope down flatly (barely convex) from the suture, 

 are very sharply carinated at the canal, the under edge of which in particular is prominent 

 and expressed ; below the canal they contract into the suture ; the base is tumid. Suture 

 strongly impressed and very distinct. Mouth quite round. Outer lip thin, regularly 

 arched. Inner lip on the body thin, and very short, regularly curved throughout, on the 

 pillar thin and patulous. Umbilicus large and pervious, but partly covered by the 

 pillar-lip. L. 0"099 in. B. 0*09. Mouth, length 0-05, breadth 0-051. 



This species has the strong lamellaa of Scissurella lamcllata, A. Ad., from Japan, but these are 

 here still stronger, with a high spire and tumid base. It has some resemblance to Scissurella umbili- 

 cata, Jeffr., but the spire is much higher, the whorls more exserted and contracted below the canal, 

 and the sculpture is quite different. 



4. Scissurella coronata, n. sp. (PL VIII. fig. 4). 



September 28, 1875. Tahiti harbour, near the reefs. 20 fathoms. 



Shell. — Obliquely discoidal, strongly ribbed and spiralled, flattened above, with the 

 apex rising like a coronet above the flat upper surface of the whorls, a largish very oblique 



1 arj&ome, belonging to a nightingale. 



