1872.] MR. A. GARRETT ON POLYNESIAN MITRID.E. 843 



the base, smooth, shining, bluish white, with longitudinal flexuous 

 brown stripes ; spire rather short, concavely conical, subacute, half 

 the length of the shell ; whorls 8-9, slightly convex, finely crenulate 

 and shouldered above, the upper ones decussated with fine longi- 

 tudinal ribs and transverse impressed striae, the latter continued on 

 the lower whorls, and becoming obsolete on the middle of the body ; 

 aperture narrow, bluish white and lyrate within ; outer lip rather 

 thin, sinuous ; columella with five folds. 



Length 16 mill., diam. 8 mill. 



Hab. Paumotu, Tahiti, Cook's, Samoa, and Viti Islands {coll. 

 Garrett). 



A very rare species, found under stones on reefs. 



33. Cylindra nucea, Gron. 



A comparatively rare species, found in sandy mud between tide- 

 marks, and occurs at all the Polynesian islands. 



The animal is diluted white, the foot and siphon margined and 

 mottled with black and white. 



34. Dtbaphus edentulus, Swains. 



A rare species, found under stones on reefs, and ranges from the 

 Paumotu to the Viti Islands. 



Owing to the animal of this shell being unknown, it has been 

 provisionally placed in the family Conidee. While exploring the 

 Samoa and Viti Islands, we were fortunate in discovering several 

 living examples, and, after a careful study of the animal, could not 

 detect any difference between it and a Cylindra. Unfortunately the 

 notes and drawings made at the time were subsequently lost in a 

 shipwreck. On plunging a living example in alcohol, the spirit 

 became much discoloured, of a fine purple, the same as when any 

 other Mitridce are placed in spirits. Its proper place in a natural 

 classification will be between Cylindra and Imbricaria. 



35. Imbricaria conica, Schum. 



A very abundant species, gregarious on shallow sand flats, and 

 ranging from the Paumotu to the Viti Islands. "We did not find a 

 single example north of the equator. 



36. Imbricaria punctata, Swains. 



A somewhat rare species, having the same range as the preceding, 

 and found in the same station. 



The animal is diluted white, with pale brown tentacles. The foot 

 is large, oblong, thin, rounded behind, and truncate in front. The 

 head and tentacles are small, the latter bearing the eyes on basal 

 enlargements. 



37. Imbricaria virgo, Swains. 



We obtained examples of this species at most of the Polynesian 

 islands. It is not abundant, and, like all the species, delights in sand 

 or sandy mud flats. 



