250 GASTROPODA. [Pectinibianchia. 



or rayed by growth-lines to the excavation above the fasciole corre- 

 sponding to the growth of the basal notch ; aperture small, quadrangu- 

 lar, terminating at the base in an obliquely twisted canal, which is 

 notched ; outer lip a little incurved, not produced below, but re- 

 curved at the origin of the canal ; columella strongly excavated above, 

 twisted below by a prominent and subcarinated fold which follows 

 the inflection of the canal ; inner lip somewhat callous, well applied 

 upon the base, and merging into the fasciole of the neck. 



Fossil from the Cretaceous. 



The columella is too much twisted and the anterior canal is too 

 long to enable Newtoniella to be confounded with Cerithiopsis, which 

 has, typically, merely a rudimentary notch on the anterior margin of 

 the aperture. (Harris.) 



1. Newtoniella stiria, Webster, 1906. Plate 14, fig. 24. 



Newtonidla stiria, Webster, T. N.Z.I., xxxviii, 1905 (1906), 307, pi. 38, 

 f. 5, , b. 



Shell acicular, pale yellow, vitreous, with numerous flat whorls. 

 Sculpture consists of 3 faintly jewelled spirals to each whorl except the 

 last, which has 4. Colour of dead shell pale yellow. Spire long and 

 subulate, much higher than the aperture ; outlines straight. Proto- 

 conch with 3 whorls, the first smooth and oblique, the 2 succeeding 

 first radially finely ribbed, then cancellated by spiral striations ; the 

 apex diminishes in diameter with the beginning of the definite sculp- 

 ture. Whorls 20, flat ; base flat, concave at the base of the canal. 

 Suture scarcely marked. Aperture quadrangular, canal sharply turned 

 to the left. Columella white, twisted. Opcrculum unknown. 



Diameter, 2 mm. ; height, 9 mm. 



Animal unknown. 



Type in the Dominion Museum, Wellington. 



Hob. Off Great Barrier Island, in 110 fathoms (type) ; Hauraki 

 Gulf, near Channel Island, in 25 fathoms. 



Genus 3. SEILA, A. Adams, 1861. 



Seila, A. Adams, A.M.N.H., vii. 1861. 130. Type: 8. dextroversa, Adams 

 and Reeve. CincleUa, Monterosato, 1884. Viriola, Jousseanme. 1884 ; 

 not of Tryon, 1887. 



Animal having a short, bror.d foot, indented in the middle line in 

 front, with a square-edged mentum narrower than the foot and ex- 

 tending beyond it. The tentacles are very short and stout, the pro- 

 boscis seldom protruded ; there is no muzzle like that of Cerithium. 

 The jaw is composed of spade-shaped, rather large, close-set horny 

 plates, the points projecting. The central tooth of radula is sub- 

 rectangular, wider than high, with 2 widely separated, strong, sharp 

 cusps, and a much feebler, shorter, and smaller one in the middle line 

 between them. The lateral is oblong, not very much wider than 

 high, and has a strong recurved cusp with 1 large and 1 small denticle ; 



