232 



resemblance, judging by figures, it bears to the recent F. tricar inata, 

 and in a less degree to the extinct S. (Ff/li.siaj impar, Deshayes; 

 from the first it is distinguished by tiie absence of a slight 

 shoulder to the Avhorls and by its conspicuous tessellated orna- 

 ment, whilst the latter species is quadrilirate and very small. 



Our Australian fossil presents many points of resemblance to 

 Acrilla, but is devoid of the disk-like base ; and as a whole the 

 characters are i-ather those of Scalarvt than of TurriteUa. 



16. Sealaria (Aerilla) inornata, s^>ec. nor. 



Shell minute, thin, very slender ; with eleven, smooth, rather 

 tumid, slowly-increasing whorls. 



Base disk-like, spirally lineate, margined exteriorly by a thread- 

 like rib ; slightly perforated. Aperture quadrately rounded. 



Dimensions. — Length, 3-75 ; width, 0-75. 



Locality. — Eocene ; Table Cape, Tasmania (2 exs.). 



17. Sealaria (Aerilla) paehypleura, -n^tc. nov. 



Shell thin, elongate-turriculate, imperforate ; ordinary whorls 

 eight, convex, separated by a moderately deep suture ; pullus of 

 two smooth rounded whorls, the first slightly angulated and de- 

 pressed. 



The ornament consists of flat spiral threads crossed by slightly 

 more-distant, thicker, and rounder costse ; the rectangular inter- 

 liral spaces, which are a little longer in a spiral direction than 

 wide, have a double row of three to four punctures ; there are 

 about 30 costa? and 15 lira? on the penultimate whorl, and five or 

 six varices on the spire. 



Base flattened, smooth, margined externally by an acute thread. 

 Aperture roundly oblong, peristome incomplete, outer lip thin. 



Dimensions. — Length, 11-5 ; width, 3 ; height of aperture, 2 -25. 



Locality. — Eocene at Muddy Creek. 



This species has a close resemblance to Sealaria reticulata., 

 Solander [S. clecussata, Lamk.); but on a comparison of actual 

 specimens, our fossil differs from the Hampshire and Parisian one 

 by its thicker costa:*, finer and more numerous spiral threads, by 

 its varices and more slender form, and particularly by the 

 punctures. 



18. Sealaria (Aerilla) eseharoides, -spec. nov. 



Shell thin, slender, imperforate ; ordinary whorls seven, rather 

 flat, tessellated ; pullus rather large, consisting of two smooth 

 rounded corrugated whorls. 



The spiral ornament consists of stout flat threads, increasing 

 from six in the posterior whorls to ten in the penultimate whorl ; 

 the spirals are crossed by slightly-oblique costal threads, usually 

 not so stout as the lira?, somewhat granosely thickened at the 

 intersections ; there are about 25 costa; on the penultimate whorl. 



