A Keview or the Land IMollukoa of Westiain Australia 
()5 
Parrhagada ferrosa sp. nov. 
Plate IV., flg'. 21. 
This name is given to the smaller shells from the same lot as the preced- 
ing as they measure 18 mm. in breadth and 11 mm. in height and are all red- 
dish as if dug oul of red earth. These generally agi'ee well with the i)roceding 
save in size, ami the onler li]i is .still more expanded and thiekemat. 
In my South Australian essay I pointed out that the vaiintion seen in 
many ca.ses was ditlieidt to determine. In this case the jiresent “species’’ may 
prove to be amply distinct liA’ing under different conditions, nr it may be an 
ecological variety only. It may even be a lioi'ecol, a name selected to desig- 
nate a time variety, that is, the shdls lame treated may be true dwarfs, brougiil 
about by climatic conditions of some ])i'eviuits season. It may be a geodeeol, 
that is, a shell living under different ground conditions, the vegetation being 
unsatistacLory for rapid and full growth, but these items can only be .solved 
by local workeis studying these animals under natural conditions. 
Parrhagada koolanensis sp. nov. 
Plate V., fig. 1. 
These shells collected on Koolan Island, i'ampi Sound, resemble very 
closely P. commodu but with the spir(' a little more elevated and the mouth 
not so much thrown! out. 
Shell subcouical, spire elevated, .sides I'ather straight, whorls little 
rounded, sutures lightly impressed, last whoil snhkeded, mouth descending, 
open, snbcii'culai', outer li]> broadly expanded all lound, columella, rellocted 
into umbilical cavitv- iiot completely closing it, though obscuring it so that only 
a wide chink is left apparent. Dead shells chalky white, but there ai'e rem- 
nants of a thin yellowish periostracum. There is no sculpture save delicate 
growth striae, the ajjcx smooth. Breadth 22 mm. ; height 19 mm. 
Ill this Purrhagtida eommoda comidex, this apjiears to be a real geo- 
graphical variant in contradistinction to the forms from the Napier Ranges 
just preceding. 
Genus AMPLIRHAG'ADA trodale 1933. 
mi\]—Amplirhagada Iredale, Rec. Auslr. Mus., Vol. XIX., p. 52, Aug. 2. 
Orthotype Helix sykesi Smith. 
This group, which I introduced as a subgenus only, appears to be of 
higher value and has a distinet range. 
Shell stout, spire elevated, whorls i'f)unded, mouth rather small, colum- 
ella with basal tooth, umbilicus more or less covered. W’liile llie species ai’e 
apparently Rliagadoid the elevation of the s])ire separates them and it ma., 
be that they are les.s closely related than would ajipear at first sight. Tie 
complexity of the group necessitates subdiiisioii, as in the past through lack 
of close examination Ihe contusion reached a .stage almost defying sim|)lilica- 
tion. 
Amplirhagada sykesi Smith 1894. 
Plate V., fig. ,3. 
1894 — Helix (Hadra) sykesi Smith, Proc. Malae. Soe. (Loud.), Vol. I., p. 
92, pi. VII., flg. 8, June. Parry Island, Admiralty Gulf, N.W. Aus- 
tralia. 
A paratype is here figured and described. Shell fairly large, conical, 
spire well elevated, whorls rounded, sutures deeply impressed, last whorl de- 
scending, well rounded though earlier a little keeled, mouth oblique, open, 
