XENOPHOEA. 253 



This common species is distinguished by its compressed form 

 and lateral apex; the "whorls rapidly enlarge, growth-lines 

 corrugating the surface ; internal plate moderately large, part of 

 the edge slightly overhanging the umbilicus. 



Some of the specimens mentioned hereunder, which are in the 

 state of casts only, are doubtfully referred to this species. 



Dimensions. — Height 7 mm. ; breadth 21 mm. 



Form, and Loc. — Pliocene and Miocene : I^ew Zealand. 



G. 9602. Specimens showing rariation in position of the apex ; 

 from Wanganui. Sir James Hector Coll. 



G. 9608. Casts in which the spire is much elevated ; from 

 Blind Bay. Sir James Hector Coll. 



G. 9620. Cast of a small specimen in a block of argillaceous 

 limestoue ; from Akuakua, east coast of Auckland. 



Sir James Hector Coll. 



G. 9626, G. 9631. Casts of large specimens having a depressed 

 spire ; from Akuakua. Sir James Hector Coll. 



G. 9627. Cast of a small example in which the earlier whorls 

 increase very rapidly ; from the Upper liedcliffe beds, Bed Cliff, 

 Rakaia river, Canterbury. Sir James Hector Coll. 



G 9698. Three examples of the adult, in one of which the 

 body- whorl is much inflated; from Parimoa. W.B.B.Mantell Coll. 



Family XEl^OPHORID^. 



Genus XENOPHORA, G. Fischer (Yon Waldheim). 

 [Museum Demidoif, vol. iii. 1807, p. 213.] 

 TUrus, ilontfort. Conch. Syst. t. ii. 1810, pp. 158-9. 



Shell trochiform, concave or flattened below ; whorls broad, 

 commonly carrying pieces of stone, shells, or other objects which 

 are agglutinated to, or imbedded in, the upper surface of the shell, 

 sometimes completely hiding it from view ; last whorl compressed, 

 keeled at the periphery ; aperture large, oblique ; outer margin 

 very oblique and sharp ; umbilicate, or narrowly rimate. 



Type. — Xenophora Icevigata, G. Fischer {Trochus conehyliophorus, 

 Giuelin). 



