S.A, NAT.. 
VOL. XVIII, No. 2. 
Specimens from Hummock Island are of Paralaoma~to^ 
but are more elevated, mouth larger, umbilicus much narrower, 
sculpture very finely reticulate and apex boldly strongly lined 
concentrically. The spire is more distinct on account of a notable 
peripheral sub-keeling. Major diameter 2 mm., height 1.25 mm. 
Paralaoma retinodes. 
1894. Charopa retinodes Tate, Trans. Roy. Soc. South Austr., 
Vol. XVIII, p.l92, November. Central Australia. 
1896. Rep. Horn Sci. Exped. Centr. Austr., pt. II, Zook, p.I87, 
pi. XVII, fig. 2, February. Reedy Creek, George Gills’ 
Range. 
Genus Excellaoma. 
1937. Excellaoma Iredale, Austr, Zook, Vol. VIII, p.31S, Mch. 
12 . 
Orthotype Helix retipora Cox. 
These species are larger than the preceding but have the 
umbilicus narrow or almost closed, the columella reflected: the 
protoconch is smooth, but sometimes obsoletely spirally striate, 
the adult regularly striate. 
Key to Species. 
Shell subconical, protoconch obsoletely spirally striate, um- 
bilicus almost closed, sculpture similar to that of 
the preceding group, but showing indistinctly a 
reticulate appearance retipora. 
Shell a little flatter, apex almost smooth and somewhat re- 
stricted, the umbilicus a little more open, the sculp- 
ture liner, the reticulate appearance emphasized; 
major diameter 6 mm., height 4 mm. 
valens sp. nov. 
Shell almost discoidal, apex still apparently smooth, the 
umbilicus almost closed, hidden by the columellar 
reflection, finely reticulately sculptured; major di- 
ameter 6 mm., height 3 mm. neta sp. nov. 
Shell flattened, apex almost smooth, umbilicus open, sculp- 
ture stronger, irregular, especially on the earlier 
whorls, and cross sculpture obsolete. 
pulleifiei. 
