FiNLAv.—New Zealand Tertiary Rissoids. 481 
(А.) * RrssoA " GROUP. 
Aperture generally suboval and entire ; basal «= hardly channelled or effuse. 
l. Shell thin; axial sculpture prominent (broad low ribs, interstices rather 
wide "um "eed "on or with arm “pial sculpture) Cai conch 
pe lobose, whorls convex an vertica 
Mi аннат WE атн "Type, H. hamiltoni (Sut.). 
. Shell ME solid, clathrate (distant fine spiral ribs, cros and 
rendering nodulous the axial ribs, which are also rather distant wide 
to 
heavily variced, peristome continuous, internally duplica 
Merelina. "Type, M. cheilostoma (Ten.-Woods). 
3. Shell similar to Merelina; protoconch smooth and glossy, dome- ерйс 
aperture thin-edged, rather simple, н ог тыне уагіх Pp 
not duplicated. inemera Туре, L. Finlay. 
(nom. p^ tor В. теда Hutt., беор.) 
4. Shell thin, t; fine and weak axial and spiral viene 
emitransparen 
ibis mens the aperture; protoconch smooth, dotis shaped ; - 
ma eese ; аа ovate- pyriform, the Кошою disconti 
nd sharp. Onoba. Type, O. si init Мар), 
5. Shell thin, translucent; cut up into weak spirals by grooves, по axials ; 
toconch smooth, papillate, whorls slightly convex; aperture sub- 
vertical, ovato- pyriform, peristome continuous, thin and sha arp. 
Subonoba. Type, S. fumata (Sut.). 
. Shell very solid ; very heavily wien pte we rahe ribs maa raised 
and flatly ro rounded, continuing о le surface. ces deep 
«id broad); protoconch smooth ine posts lirate ?) ; "whois « pest Ч 
aperture ps heavily thickened, peristome continuous, ' 
duplicated Lironoba. Type. X Sr ie 
s pe Kerek ; strong spiral keels, the intervening spaces axia 
ions; protoconch spirally striate; whorls a MEM 
Reed unded ; peristome continuous, thick and blunt. 
Anabathron. Type, A 
e 
~J 
. contabulatum Frfid. 
8. Shell solid ; ee not prominent, and when present generally confined 
to the lower whorls, e whole surface may be smooth, or traces of 
spiral Sedeta ent; there may be flattish oblique axials 
on the lower whorls; there may be a subobsolete sculpture of axial 
ribs cross y spiral cords; or there ma w spira о 
Both axial and spiral ribs, when present, are low and flatly rounded, and 
often almost o Protoconch all coni smooth;  whorls 
t; aperture highly distinctive, perpendicular, , with 
a narrow, rather sharp, and often edge, but much онаа 
internally, no exterior varix ; tome €— continuous 
reflected all round. Estea. Туре, E. Merino. (Webster). 
9. Shell thin; sculpture —À absent t (when i confined to micro- 
scopic spiral grooves); protoconch small, globose, smooth; whorls 
convex, suture often fond below ; pete subcircular, peristome 
gen эрэг бм discontinuous, thin and 
Notosetia. Type, N. neozelanica (Sut.). 
10, Shell ау thick, pupoidal; sculpture inconspicuous (smooth, spirally 
зан г ridged) ; protoconch large and globose ; whorls ые convex, 
risto 
ongate e 
remm aed the inner lip produced forward iion a sunken at г behind 
mphithalam Type, A. sa Carp. 
ll. Shell rather hm "e ан cylindrical ; Vases REA (but strong 
wth-li nt); protoconch large and globose, often pro- 
tuberant, Vie slightly convex, very elongate; aperture xp to 
that of Amphithalamus but narrower and more — 
Epigrus, Туре, Е. ischna (Tate). 
16—Trans. 
