231 



G. 5536. Example in which the whorls are regularly convex 

 and not angulate ; from Muddy Creek. Purchased. 



G. 9477. Several specimens ; from Muddy Creek. Purchased. 



Genus TRIFORIS, Deshayes, 

 [Coq. Foss. Paris, t. ii. 1833, p. 429,] 



Shell small, turriculate, frequently attenuated at its anterior 

 extremity ; almost always sinistral ; aperture small, terminated 

 by a short anterior canal. 



Type. — Triforis plicatiis, Deshayes. 



Triforis planata, Tenison-Woods. 



1880. Triforis planata, Tenison-Woods, Proc. Linn. Soc. N.S.'W. vol. iv. 



p. 6, pi. i. fig. 12. 

 1893. Triforis plamdata, Tate and Dennant, Trans. Key. Soc. South Aust. 



vol. xvii. pt. 1, p. 222. 



This species is readily distinguished by the comparative smooth- 

 ness of the whorls, which are spirally lineated anteriorly, and 

 crossed by faint closely-set longitudinal costae, the points of 

 junction being granulate ; aperture quadrate ; columella twisted ; 

 anterior canal bent. 



Dimensions. — Length 19'5mm.; breadth 3"5 mm. 



Form, and Loc. — Eocene : Muddy Creek, Victoria. 



G. 9464. Two examples of the neanic stage of growth, and 

 one of the ephebic. Purchased. 



Genus DIASTOMA, Deshayes, 



[Desc. anim. sans Vert. 1861, vol. ii. p. 411.] 



Shell turriculate, varicose, with a sharp spire ; aperture ovate, 

 oblique, canaliculate, and detached behind, sinuous but not 

 canaliculate in front ; columella slightly concave, covered by 

 a thin, shining, and somewhat detached plate, or an affixed 

 callosity, and carrying, towards the middle, an oblique plication 

 not always well marked. 



