Fintay.—New Zealand Tertiary Rissoids. 493 
species, and frequently retain their colour-bands. One or two juvenile 
shells in the author’s collection, which had been doubtfully named “ R. vana 
Hutt." proved to have exactly the same protoconch as specimens of 
examination of the type a ecd Bee зе Mr. Marwick, by Miss 
Mestayer), so that the name R. vana Hutt. must be dismissed from faunal 
lists. Potamopyrgus speleus (Frauenfeld) SÉ been found by the author 
in exactly similar circumstances, occurring with Pliocene fossils from 
Castlecliff. 
KEY TO GENERA. 
Aperture deeds edge e often reflected, much thickened ее, 
rior vari Estea. 
ome with the edge Gither thin | or MH. €: means of an «егы 
(1) Very strong = cords .. m is Rf .. Lironoba. 
(2.) Clathrate 
A.) нара spirally lirate, dull e x .. AMerelina. 
(B.) Protoconch smoot y NS .. Linemera. 
(A.) Aperture rotund, simple ; spirals rarely prese: Haurakia. 
(B.) реше oe se channelled below spiral 
genera т Rissoina, 
(4.) Surface almost smo 
(A.) Shell white, highly polished, inr channelled below .. — Nozeba. 
(B.) gens eee — tall and cylindric = — sepa- 
he body-whorl by a groov Epigrus. 
(C.) Shel smooth or маи ава irate, ньо convex, 
mple, ro ANotosetia. 
(D.) Shell сае whorls go ч ог лөм aperture ees 
ss pyriform, slightly channelled belo Dardanula, 
KEY TO SPECIES, 
Genus Haurakia. 
1. About 20 axial ribs pe whorl, with an infrasutural seers 
whorls flattish H. mixta Finlay. 
2. About 30 wise ст per Who with faint spirals between, 
whorls con H, oamarutica Finlay. 
Genus Linemera. 
1; € аы spiral ribs close to the lower suture, with а 
oth band between, also an infrasutural groove L. interrupta Finlay. 
2. э peak and tater: d etum per whorl, interstices linear L. minuta Finlay. 
3. Four distinct b spirals per n interstices much 
wider ; sd iet 18 per whorl . L. pukeuriensis Finlay. 
4. Six very fine spirals per whorl, нне с "idee; ў 
axials about 36 per whorl L. awamoaensis Finlay. 
Genus Lironoba. 
l. Five Be sabe ribs per whorl, with 4 more on the р» inter- 
about three times their width L. polyvincta Finlay. 
2. Dae аа ribs рег whorl, with 5 more оп beso. juter- 
stices about twice their width L. charassa Finlay. 
