700 



EEY. K. BOOa WATSON ON THE 



carried across the short juuctioii with the body by a thin nacre- 

 ous callus, wliicli is continued within and is, in fact, the comple- 

 tion of the wliorl into a tube. Inner lip slightly thickened, 

 curved, just barely reflected. Umhiliciis wide and pervious, ex- 

 posiDg all the whorls, and strongly cross-hatched within by the 

 spiral and longitudinal threads. Operculum very thin, clear, and 

 bright, with about eight faintly delined turns and marked with 

 microscopic concentric lines. H. 0"64. B. 0'87, least 0"62. 

 Penultimate whorl 0-18. Mouth, height 0-43, breadth 0'4. 



This shell slightly recalls Helix ericetorum, MiilL, but much 

 more closely resembles some of the West -Indian land-operculates, 

 such as Aulopoma. There is a Margarita umbilicalis, Broderip, 

 which it is like, so far as one can judge from Chenu's figure 

 With its continuous peristome it very much recalls a Gyclostrema, 

 all the more so that it is less pearly within, less nacreous and 

 more chalky, and less globosely conoidal than Margaritas usu- 

 ally are. 



• 6. Teochus (Maegaeita) ciiAEOPUS, (xojOOTTos, light blue.) 



St. 149 (9). Jan. 29, 1874. Lat. 49° 16' S., long. 70° 12' E. 

 Kerguelen Islands, W. Christmas Harbour. 105 fms. 5 specimens. 



Shell. — Globosely conical, like a Cyclopliorus, ihm^ translucent, 

 umbilicated, iridescent, banded, spirally studded ^ith irregular 

 interrupted, long, narrow, sharp tubercles. Sculpture. Of spiral 

 threads there are from twenty-five to thirtj^-fivc, shai:p]y projecting, 

 rounded, and fine on the last whorl; of these, from three to seven are 

 feebler than the rest ; those on the base are continued within the 

 mouth. The interstices arc much broader tlian tlie threads. The 

 whole surface is also fretted by microscopic spirals and stronger 

 longitudinals wliich follow the oblique lines of growth. Of the 

 threads, six to thirteen appear on the penultimate whorl ; they begin 

 with the second whorl, and there the longitudinals are rather 

 disproportionately strong and regular. The embryonic apex is 

 faintly but coarsely tubercled. Colour yellowish W'hite, shot on 

 the upperside with a dark iridescence ; the spirals are black, 

 clouded, and broken with oblique longitudinal streaks of white. 

 The spire is high and turreted. The apex, porcellanous and scarcely 

 iridescent, is small, high and mammillate,and consists of the one em- 

 bryonic whorl, which is a little turned up on its side. Whorls 6, 

 of gradual and regular increase, rounded, near the apex a little an- 

 gulated by one of the spirals. Suture well marked, angulated^ 



