S.A. NAT., VOL. XIV. 
24. South AnstraUon Slirlls. XovKMf’.ER, 1932. 
Odostomia Fleming 1813 (= Odontostoma Pb.ilippi): 
Odous=a tooth, stomata mouth. Oval, conoidal or turriculate, 
umbilicate; typically smooth; protocouch sinistral of one or two 
Turns: suture well marked; mouth oval; peristome mostly dis- 
continuous; columella with a single tooth-like fold; operculum 
horny, lamellar, subimbricated, with a median spiral groove, 
inner margin indented. Type — Turbo plicatus.,. Montagu 
(South of England). Animal elongated, head large and robust, 
bearing two conical tentacles, with eyes at their bases; foot 
depressed, truncated in front; mentum anteriorly bilobed. The 
shells are very small, usually smooth, and are found at low- 
water mark beneath loose stones, and at the base of small 
seaweeds in rock-pools; others are found in the laminarian zone, 
and some occur in deep water; some again live in brackish water. 
They subsist on soft animal substances, the radula being without 
teeth. Certain Northern species are commonly found on the 
*‘ears” of Pectens, and, from their habitual proximity to the 
e.tcretory passage of the scallop, it is inferred that they subsist 
on its faeces. The species are prolific and widely diffused. The 
sinistra! protocouch is a constant feature of the gems. In the 
S,.A. Museum are many new species from Southern Australia yet 
to be described. 
O- angasi Tryon 1886 (= 0, lactea Angas 1867, prcocc. 
Dunker). “Angas' Odostomia.” Elongate, rather thin, 
shining; white; smooth; whorls six, flattened; suture im- 
pressed; mouth small, ovate, somewhat produced anteriorly, 
one third the length of the shell; outer lip thin, simple; columella 
with one strong, oblique fold. Height 6, diam. 2 mm. Beach, 
MacDonnel! Bay, Port Willunga; dredged Gulf St. Vincent, Cape 
Jaffa, down to 130 fathoms. (Type locality — Port Jackson, 
N.S.W., in deep water.) 
O. australis Angas 1871 {Agatha) “The Southern Odos- 
tomia.” Acuminate, solid; whitish; decussated with axial ribs 
and more numerous spiral ridges, the axial ones evanescent at 
the base; whorls nine; sutures impressed; mouth nearly circular, 
entire. Height 10 diam. 2 mm. Rare. Beach — Gulf St. Vincent, 
Port Macdonnell; also dredged Beachport, St. Francis Island, 
15-40 fathoms. (Type locality — Port Jackson,. N.S.W.) South 
Australian specimens average a little shorter and broader than 
the type, though apparently the same species. 
O. deplexa Tate and May 1900. PI. 1, fig. 8. “The 
Embracing Odostomia,” in allusion to the concealed protocouch. 
Elongate oval, moderately stout, shining; white; smooth, except 
for microscopic growth lines; protocouch concealed, except the 
