38 
Tom Ieedale. 
twenty-iive, the tine i-itdials erossetl by fine eoneenrrie threads suggesting a 
faint dec-ussation which is faintly seen on base. Tin' uinbilicirs narrow deep, 
about one-foiirth the breadth of the l)ase, tlie mouth descending, subcircular, 
outer lip thin, columella slanting, reflected. Breadth 1.5 mm; height 1 mm. 
Naugeenan via ilerredin, ^V.A., collected by E. Sedgwick. 
Westralaoma aprica sp. uov. 
Plate III., fig. 7. 
A deiiressed Paralaomid form lacking strong radial ridges, and the fine 
radials are cross(‘d by a subordinate concentric threading producing a finely 
decussate a])pearanc(> which is more notable in the undulical cavity, which is 
about one-third the breadth of the base. Shell subdiscoidal, spire little 
elevated, ape.x finely concentrically striate, month subcircular, outer lip thin, 
columella a lillle reflected. Breadth 2 mm.; height 1.1 ram. 
Nangeennn via .Merredin, W.A., collected by E. Sedgwick. 
Genus INSULLAOMA Trcdale 1937. 
1937 — I'lisullaomd Iredale, South Austr. Naturalist, Yol. XV III., p. 19, Sept. 
30. Ilaplotype Parahtoma riddle! Iredale. 
This name was introduced .snbgenerically for the South Australian forms 
of Pandooma, as these had the apical whorls spirally striate or even lirate, 
whereas the fyi)ical form had the apex smooth or radially fiiudy striate. Thu 
shell se](‘cted as type of IfisuUiionid^ riddle!, was soTiiewhat elevated, umhiHciis 
narrow, finely reticulately sculptured, and had the a|)ox boldly strongly oon- 
cientrieally lined. Of course this cannot be seen withoul a .sli'ong lens. More- 
over, in this ease there was a pei'i|)heral subkeeling. The recognition of a 
Western Australian form agreeing in all these features has led to the admis- 
sion of this group geuerieally. 
Insullaoma predicta sp. nov. 
Plate 1., fig. 22. 
Anotln'r of the discoveries of Mr. Sidney W. Jackson at Bow River-, 
South ConsI, especially as it appears to l)e a true Ttisiillaoiiia. Shell small, 
subdiseoida], spire short, brown, undriliens narrow. The apical two whorls 
are large and bulbous, and are coarsely s])irally lirate: the adult whorls are 
closely flue radiate, with a line eoncenlrie striation ei'os.sing it, the last whorl 
subkeeled. The mouth is subcircular, outer lip tliiu, columella a little re- 
flected, the umlrilicus oiien, narrow, less than one-third the width of the base. 
Bi-eadth 1.25 mm. : height .6 mm. 
Found alive under karri bark at foot of karri tree on edge of wattle 
scrub. 
Genus G-KATILAOMA gon. nov. 
Ty]re G-. cara sjr. nov. 
Plate 1., fig. 20. 
This beautiful little shdl collected by Tlr. Sidney IV. Jackson at the Bow 
River, South Coast, suggests an elevated relation of Westralaoma, as it is sub- 
conical with similar radials, but has a cross sculpture of crosslining, the 
umbilicus being nan-owed. 
As Westralaoma is constant in form it seems better to name the present 
form separately than r-efer it to that genus, and thus spoil the homogeneity 
of the group. 
