137 



.angle of the aperture, thence gradually attenuated ; spirally 

 grooved throughout. 



Aperture narrowly elliptic ; lip sharp ; columella with five 

 plaits, increasing in size from the front. 



Dimensions. — Length, 55-5; breadth, 13; height of last whorl, 

 ,26-5. 



Locality. — Lower beds at Muddy Creek. 



The species was established on juvenile examples, which I have 

 traced up to the moderately large specimen herein figured. The 

 figure of the type does not correctly represent the shape, being 

 much too broad. 



2. Mitra Dennanti, spec. nov. Plate iii., fig. 3. 



Shell moderately stout, fusiform-biconic ; spire short, ending 

 in a blunt apiculate point ; pullus of four whorls, the anterior one 

 large, much embracing the next, the last turn very small sub- 

 globose. 



Ordinary whorls four, convex, separated by a narrow^ shallow 

 channelled suture, with a rounded appressed shoulder, regularly 

 spirally grooved ; about twelve grooves on the penultimate whorl, 

 crossed by close-set strife, which produce the appearance of linear 

 oblong punctures in the grooves. 



Last whorl somewhat ventricose, the median portion smooth or 

 spirally striated ; posteriorly and anteriorly spirally grooved, and 

 neatly punctated. 



Aperture elongate-oval, outer lip thin ; columella with four 

 plaits, the posterior one the largest. 



Di7nensions. — Length, 33 ; breadth, 16 ; length of aperture, 

 22. The corresponding measures of a very large specimen are 

 47, 20, and 30. 



Locality. — Lower beds at Muddy Creek (J. Dennant I) 



3. Mitra dictua, Tenison Woods. Plate iv,, flg. 9. 



Reference. — Proc. Lin. Soc, N.S. Wales, plate iii., fig. 7, p. 8, 

 1879. 



Shell rather thin, elongate-fusiform \ spire longer than the 

 aperture, ending in a conoid pullus of three smooth, slightly con- 

 vex, regularly increasing turns. 



Whorls eight, excluding the pullus, nearly flat, separated by a 

 linear impressed suture, the anterior ones by a narrow chan- 

 nelled suture with a rounded shoulder. The first and second have 

 thick costse and spiral linear grooves, the next three are spirally 

 grooved and obscurely punctated, the whole surface crossed by 

 raised curved threads ; thence the spiral grooves gradually merge 

 into threads or stripe. 



Last whorl with a few slender striae at the shoulder, spirally 



