S.A. NAT.. 
VOL. XVIII, Xo. 2. 
I3.V TOM IREDALK. 
3fL 
Semotrachia subsecta. 
1879. Helix subsecta Tate, Trans. Proc. Phil. Soc. Adelaide, 
South Austr., 1878-9, p.l33, pi. V, ff.2,a b, after Oct. 
Port Wakefield, South Australia (Mrs. Kreusler). 
This shell appears to resemble basedowi but with a little 
more elevated spire but the locality &eems incongruous. Perhaps 
it was only sent, not collected, from Port W'^akefield. 
Semotrachia eyrei. 
1876. Helix eyrei H. Adams and Angas, Proc. Zool. Soc. (Lond,). 
1876,‘p.489, pi. XLVII, figs. 10-12, Oct. 1. Shores of 
Lake Evre, Central Australia. 
1877. Helix eyrensis Martens, Zool. Record, 1876, Moll, p.44, 
emendation only. 
W ith flattened top and wider umbilicus, the mouth less 
oblique and open, this species stands somewhat apart especiallv 
as the sculpture has become obsolete. It may not be closely 
allied to any other species but appears to be common in the type 
locality. Specimens have been collected as far south as Mt. 
i-yndhurst but otherwise it appears to be restricted to the shores 
of Lake Eyre. It may be given the new subgeneric name, 
Lacustrclix, as it is anomalous however it is judged. 
Genus Vidumelon. 
1933. V'ldumelon Iredale, Rec. Austr. Mus., \'ol. XIX, p.Sl, 
August 2. 
Orthotype Hadra zvattii Tate. 
This curious shell cannot be easily placed in either family, 
the Hadridae or the Xanthomelontidae, from conchological char- 
acters as these are dissimilar from either. The shell is subdis- 
coidal, spire very little elevated, whorls numerous, umbilicus 
very narrow but not hidden by the columella, mouth elongate 
much wider than deep, basal faintly tuberculate, mouth edge 
reflected, sculpture of fine slanting striae, periphery rounded. 
Vidumelon wattii. PI. II, fig. 6. 
1894. Hadra zvattii Tate, Trans. Roy. Soc. South Austr., \'oI. 
XVIII, p.l92, November. Central Australia. 
1896. Thersites (Badistes?) zvattiiTatQ, Rep. Horn. Sci. Exped. 
Cent. Austr.. pt. II, Zool., pi. XVIII, fig. 12, Februarv. 
Maude River, Hart Ranges C.A. 
