Hutton. — On the Silt Deposit at Lyttetton. 411 



Odostomia sherriffi, sp. nov. 



Shell subulate, tapering : whorls fifteen, smooth, flattened and polished, 

 the suture deep. Aperture ovate ; peritreme not continuous ; columella 

 with one strong plait. 



Length, "55 inch ; breadth, "17 inch. 



Named after Mr. Gr. Sherriff, of Wanganui. 



Trochita infiata, sp. nov. 



Shell subglobose; whorls two and a half rounded; the last inflated, 

 with four or five distant, narrow, spiral ribs crossed obliquely by lines of 

 growth : apex lateral. Aperture ovate, the lamina concave. 



Height *4 inch. Length of aperture -88 ; breadth -72. 



This species has externally the appearance of a Natica, but the surface 

 is not polished. 



Anihora conica, sp. nov. 



Shell conical, high ; whorls seven, slightly convex, with fine spiral 

 moniliform ribs, about eight on the penultimate whorl ; suture deep ; base 

 of the last whorl spirally striated with moniliform striaa, the angle rounded. 

 Axial cavity deep, smooth, conical ; columella with a slight posterior fold. 



Height # 84 inch ; breadth *84 inch. ' 



This species has the smooth axial cavity of A. tiarata, but it is larger, 

 higher, the granulations finer, and the basal angle much more rounded. 



Note. — In addition to these new species there was in the collection a 

 specimen of what I take to be Siphonaria fuscozonata, Angas (P.Z.S., 1865, 

 p. 56), which appears to be the same as Fusus minutisquamosus, Keeve. 



Art. L. — Note on the Silt Deposit at Lyttelton. By Prof. F. W. Hutton. 



[Read before the Philosophical Institute of Canterbury, 6th April, 1882.] 

 In cutting back the hill on the west side of Lyttelton Harbour to make room 

 for the dock, an excellent section has been exposed of the silt deposit and 

 the rocks underlying it. An uneven surface of volcanic rocks is covered by 

 the silt, which is distinctly stratified, and dips at an angle of 8 degrees to 

 the north-east, that is towards the harbour. In 1878 the cutting behind the 



Fig. 1. a, silt deposit ; b, volcanic rocks. 





