Hurron.—On New Zealand Land Shells. 179 
Hab. Titirangi, Auckland (T. F. Cheeseman). 
I place this species in Gerontia from the general appearance of the shell, 
but I do not know the animal nor the dentition. It differs from G. 
pantherina in being more convex, in the epidermis not being plaited, in 
being more coarsely striated, in the right margin descending, in the 
aperture being less oblique, and in its colours. 
AMPHIDOXA PERDITA, n. s. Pl. xi., figs. o and Q. 
Shell thin, shining, pellucid, depressed, umbilicated ; colour pale olive 
horny. Spire convex; whorls 33-4, rapidly increasing, rounded, finely 
irregularly striated ; suture deeply impressed ; umbilicus narrow, pervious ; 
aperture oblique, lunately circular ; peristome thin, the right margin joined 
closely to the next whorl. Greatest diameter :23, least :2; height :18 
inch. 
This shell differs from H. chiron in being higher, the umbilicus narrower, 
and the right margin of the peristome not advancing. From H. novare it 
differs in being striated, in the suture being impressed and the spire convex. 
From A. cornea it differs in being umbilicated. 
Animal with the mantle central, slightly reflected over the peristome of 
the shell; tail pointed, depressed, with a mucous gland. ‘Colour dark 
slate-grey, the mantle marbled with black and white ; sole of the foot dirty 
yellowish. 
Jaw arcuated, narrow, not tapering, smooth, but with 80 or 40 delicate 
rounded ribs. 
Dentition, 20-1-20. Laterals 6 or 7. 
Central tooth rectangular, longer than broad ; the reflexed portion 
covering two-thirds of the base; the sides concave, with a cutting point on 
each; the apical cutting point moderate. Laterals like the central; but 
the cutting points larger, and the outer margin of the reflexed portion more 
excavated. Marginals quadrangular, broader than long, the inner with 
three large cutting points; the outer with a single broad dentated cutting 
edge ; the last without any cutting edge. 
Hab. Greymouth (R. Helms). 
AMPHIDOXA JACQUENETTA, N. 8, PI. x., fig. c. 
Shell perforate, flattened, keeled; colour pale brown. Spire flat, or 
very slightly convex; whorls 24, rapidly increasing, very slightly convex, 
the last acutely keeled and rounded on the lower surface ; smooth, delicately 
. striated with growth-lines, the surface very finely and irregularly diagonally 
reticulated, and crossed with faint distant spiral strie ; suture impressed ; 
umbilicus very narrow ; aperture (?). Greatest diameter :2, least :12; 
height *06 inch. 
