125 



Locality. — Lower beds at Muddy Creek. 



This species is more lanceolate tlian T. Wbodsii, with 

 convex whorls ; though having the same form of ornament, it 

 has the anterior convexity of the last whorl uninterrupted, and 

 the nuclear whorls are different. 



14. Triton cribrosus, spec. nov. Plate v., fig. 5. 



Shell elongate-fusiform, with a very high, gradually attenu- 

 ated spire of eight gradated whorls, terminating in an apex of 

 two an a half rounded whorls, with a very small mamillate tip, 

 the anterior whorl globose and finely spirally lirate. 



Spire whorls, excepting nuclear ones, convex, narrowly trun- 

 cated at the periphery by two stout fiat ridges, and the pos- 

 terior slope broader and less abrupt than the anterior slope ; 

 a moderately strong post-medial ridge encircles the posterior 

 slope, and there is a similar one at the anterior suture. The 

 concave interspaces are encircled each with two or thre& 

 similar but smaller threads. The whole surface crossed by 

 thin, six or seven, intervariceal costulations which are knotted 

 at the junctions with the lirse, and distantly transversely 

 striated. 



Varices at about four-fifths of a whorl, compressed, rather 

 high, with four broad crenate-serratures. 



Last whorl quadrately convex, somewhat rapidly attenuated 

 into a long, slightly curved and reverted beak ; feebly costu- 

 lated on the base. Outer lip sulcated within ; inner lip thinly 

 and narrowly adpressed over the columella ; columella slightly 

 arched, with an oblique ridge terminating at the point of the 

 pillar. Canal as long as the aperture, rather narrow, slightly 

 bent to the right, and reverted. 



Length, 34 ; breadth, 15 ; length of aperture and canal, IS'5. 



Localiti/. — Clayey green-sands, Adelaide bore. 



15. Triton crassicostatus, spec. nov. PI. xi., fig. 4. 



Shell elongate-ovate, with a moderately high regular spire 

 of eight gradated whorls, ending in a mamillate apex of about 

 four rounded smooth whorls, with the tip very small and 

 slightly exsert. 



Spire w^horls (excepting nuclear ones) of regular rapid in- 

 crease, slightly concave at the shoulder, angulated at the keel, 

 with a very slight contraction towards the anterior suture. 

 Ornamented with about ten equidistant flatly rounded liras ; 

 the intervening much broader furrows closely and sharply 

 transversely striated. The transverse ornament consists of 

 six intervariceal costje, which are raised into blunt serratures 

 on the keel ; the varices are compressed, elevated, crenulated 

 on the margin, situated at two-thirds of a w^horl. 



