Mitrella.] GASTROPODA. 433 



lines fine, straight. Colour light-yellowish. Spire subulate, a little 

 higher than the aperture ; outlines nearly straight. Protoconch small, 

 papillate, the nucleus somewhat oblique. IVfwrls 5, regularly increas- 

 ing, very lightly rounded, the last convex, contracted at the base. 

 Suture linear, false-margined below. A fieri are narrow, angled above, 

 slightly contracted below, but Xvithout a canal. Outer lip thin and 

 sharp, smooth inside, lightly convex, somewhat contracted below. 

 Columella vertical, a little convex. Inner lip narrow, smooth, spread- 

 ing as a very thin glaze over the lightly arcuate parietal wall. Oper- 

 culum unknown. 



Diameter. 1-8 mm. ; height, 4-5 mm. 



Animal unknown. 



Type in my collection. 



Hob. Near the Bounty (type) and the Snares Islands, in 50 fathoms 

 (Captain Bollons) ; Foveaux Strait, in 15 fathoms. 



3. Mitrella paxillus, Murdoch. 1905. Plate 19, tig. 15. 



Columbella paxillus, Murd., T.N.Z.I., xxxvii, 1904 (1905), 224; pi. 7, f. 14. 

 Pyrene paxillus, Murd. : Iredale, T. N.Z.I., xl, 385. 



Shell small, subulate, slender, smooth, brown. Sculpture consisting 

 of a few small spirals at the anterior end of the body-whorl ; a few 

 irregular microscopic spiral lines may be present on some of the whorls, 

 but very often they are wanting ; a few axial riblets, periods of rest, 

 are visible on the spire-whorls. Colour light brown or reddish-brown 

 or almost black, the suture occasionally a little lighter. Spire subulate, 

 about 1| times the height of the aperture : outlines straight. Proto- 

 conch of 2 convex whorls, smooth and polished, papillate. Whorls 5| 

 to 6, lightly convex, the last lightly angled at the periphery ; base 

 very little contracted. Suture impressed. Aperture short, oval, angled 

 above, somewhat narrowed below, but without a canal ; base very 

 lightly notched. Outer lip strongly arched, smooth within, sharp. 

 Columella lightly arcuate, vertical, somewhat twisted below. Inner 

 lip narrow and thin, spreading over the faintly concave parietal wall. 

 Operculum unknown. 



Diameter, 2 mm. ; height, 5 mm. (type). 



Animal unknown. 



Type in the Dominion Museum, Wellington. 



Hob. Whangaroa Harbour, type (C. Traill) ; Whangarei Heads ; 

 Takapuna ; Manukau Harbour ; Kawhia ; New Plymouth ; Lyttelton 

 Harbour (Iredale). 



Remark. Specimens I collected near Tamaki Heads are not so 

 slender as the type ; adult specimens are 2-5 mm. by 6 mm. 



4. Mitrella pseudomarginata, Suter, 1908. Plate 19, fig. 16. 



Mitrella pseudomarginata, Suter, P. Mai. S., viii, 1908, 179, pi. 7, f. 4. 

 Shell small, subulate, smooth and polished, translucent, whitish 

 with light-brown zigzag markings. The only sculpture consists of a 



