113 



Length (incomplete), 19; breadth, 11; length of aperture 

 and canal, 12. 



Locality. — " Oyster banks," Aldinga Bay. 



This purpuroid fossil is placed under Troplion, because of its 

 close resemblance to the living Purpura Flindersi, Ads. and 

 Angas, which Tryon has removed to TropJion, of which it has 

 the characteristic operculum. From T. Flindersi it is distin- 

 guished by its elongate shape and rounded body whorl. 



FAMILY PUF^^UKACEA. 



GrEISTS EaPAI^A. 

 1. Rapana aculeate, spec. nov. Plate ii., fig. 8. 



Shell pyriformly ovate, thick ; whorls eight, spire mode- 

 rately elevated, terminating in an obtuse apex consisting of 

 two smooth globose whorls. 



Whorls angularly convex, anteriorly truncated and bicari- 

 nated ; last whorl ventricose, roundly and narrowly truncated 

 on the periphery, abruptly attenuated into a short broad beak. 



The transverse ornament consists of plications and closely- 

 set appressed lamellae. The number of costse on the body 

 whorl is seven, on the median portion of which they are high 

 and narrow, but evanescent on the base of whorl, and ante- 

 riorly they are ill-defined angular ridges. There are usually 

 eight plications on each of the spire whorls (excluding the 

 apical ones) . The plications are raised into vaulted scales on 

 the posterior angulation, and in young shells the scales are 

 elongated, reverted, hollow spines. 



The spiral ornament consists on the spire whorls of slender 

 threads much obscured by the transverse lamellae ; but a few 

 distant lirie are conspicuous on the medial portion of the body 

 whorl . Aperture ovate, peristome continuous ; outer lip some- 

 what flatly expanded anteriorly, lirately ridged within anterior 

 to the carination of the whorl; inner lip erect, concave medially. 

 Umbilical fissure margined by an elevated rounded keel. 



Immature shells of about 30 millimetres are exceedingly 

 like Murex Eyrei, and are imperforate ; they may be distin- 

 guished by the larger pullus, the higher sloping posterior area 

 of the whorls, and the few stouter lirse on the anterior part of 

 the body whorl. 



Length, 50; breadth, 34; length and breadth of aperture, 21 

 and 14; length of canal, 12. 



Localities. — Blue clays at Schnapper Point and lower beds 

 at Muddv Creek, Victoria. 



