HORN EXPEDITION-MOLLUSCA 
187 
ai'e about 150 in nuiiibcr, and curve gently backwards on the peripliery, thence 
nearly straight to the umbilical margin, and continued perpendicularly on its side; 
the costie are slightly wider than the interstitial furrows, which are apparently 
devoid of parallel striie or transverse threadlets. 
Dimensions. —Diameter, 2 ; height, '75 (vix.) 
Locality. —At Penny Springs, in George Gill’s Range, on damp eai'th in the 
shade of cycads. 
Affinity. —This interesting addition to the pulmonate fauna of Australia closely 
resembles Helix antialba, Beddome, Proc. Roy. Soc. Tasmania for 1879, p. 23, 
1880, which has been figured and amply diagnosed by Hedley in Proc. Lin. Soc., 
N. S. Wales, 1892, pi. i, tigs. 5-8, p. 166, from which it differs by its flat spire, 
very much smaller umbilicus, and by the absence (apparently) of secondary 
sculpture. 
Endodonta (Chapopa) planorbulina, sp. nov. (Plate XVII., Fig. 3.) 
Shell flatly discoidal ; spire flat but not sunken. Whorls three and a half of 
moilerately rapid increase ; suture well-dehned but not channelled. Last whorl 
inconspicuously elevated at the suture, thence flatly convex to the narrowly- 
rounded periphery, merging into the tlatly-convex base; umbilicus wide and 
perspective, about one-third the width of the shell. Aperture not descending, 
lunate ; peristome thin, margins not callously joined. 
The sculpture consists of very narrow, ele\'ated, arched riblets, which on the 
last whorl are about one hundred, and extend from the suture to the umbilicus. 
I'liey show here and there a tendency to bifurcate at the periphery ; the much 
wider concave interspaces are smooth. 
Dimensions. —Major diameter, Do; height, ‘5. 
Locality. —Five examples among M. heniiclausa, probably at Palm Creek, 
Krichauff Range. This species is one of the smallest and is the most depressed of 
the genus. It resembles C. lottah, but is more depressed, with a flatter base, 
finer and closer riblets. C. gade?isis is a stouter shell with a channelled suture. 
Flammulina retinodes, Tate. (Plate XVIL, Fig. 4.) 
Reference.— Charopa retinodes, Tate, Trans. Roy. Soc. S. Aust., vol. xviii., 
p. 192, 1894. 
Kk'l 
