142 



17. Mitra clathurella, spec. nov. Plate viii., fig. 8. 



Shell small, fusiformly ovate, with a sliort obtuse pullus. 

 Whorls four, excluding pullus, convex, margined and concavely 

 ■depressed at the posteiior suture ; ornamented with rather slender 

 oblique costa? (about 20 on the penultimate whorl), fine trans- 

 verse strife, and spiral threads, anterior to tlie antesutural depres- 

 sion (six on the penultimate whorl). 



Last whorl with slender cost?e, tessellated by spiral threads, the 

 inter-depressions finely transversely striate. 



Aperture narrow-oblong, contracted in front to a short broad- 

 ish, bent, and slightly reverted beak. Outer lip slightly ascend- 

 ing on the penultimate whorl, slightly emarginate at the suture, 

 smooth within ; columella with four rather distant transverse 

 plaits. 



Dimensions. — Length, 6 ; breadth, 2-75 ; length of aper- 

 ture, 4. 



Locality. — Lower beds at Muddy Creek. 



This species has much the aspect of a Clathurella. 



18. Mitra biornata, spec. nov. Plate v., fig. lo. 



Shell rather thin, narrow-fusiform, ending in a blunt pullus of 

 one and a half smooth turns. Whorls, five, excluding pullus, 

 convex, separated by an impressed suture ; sculptured with slen- 

 der, flat, spiral threads, and transversely finely striated, the three 

 posterior whorls transversely plicate ; there are about 1 8 spiral 

 threads on the penultimate whorl. 



Aperture narrow-oval, contracted into a short wide beak ; 

 outer lip thin, crenately wrinkled at the front, lirate within ; 

 ■columella with five plaits, the two posterior and larger ones bi- 

 plicate. 



Dimensions. — Length, lO'S ; breadth, 3-5; leng-th of aper- 

 ture, 5, 



Locality. — Lower beds at Muddy Creek. 



19. Mitra subcrenularis, spec. nov. Plate v., fig. 6. 



Shell rather thin, broadly fusiform, ending in a blunt papillary 

 pullus of two and a half smooth turns. Whorls, five, excluding 

 pullus, nearly flat, and slightly flattened at the anterior suture ; 

 sculptured with linear spiral grooves, and on the posterior whorls 

 with transverse plications, which end posteriorly in granular 

 crenatures. 



Last whorl somewhat ventricose behind, spirally lirate, but tlie 

 costee are obsolete, or reduced to mere crenulations at the suture. 

 Base rapidly attenuated in a short narrow beak. Outer lip 

 thin, smooth within ; columella with four distant plaits. 



Dimensions. — Length, 11 ; breadth, 4*5 ; length of aperture, 6.5. 



Locality. — Clayey-green-sands, Adelaide bore. 



