195 
Taken in King George Sound on the beach, and in 10 to 15 
fathoms very many, and in 28 fathoms a few; on Bunbury 
beach, 3; in Geographe Bay, 15 fathoms, 2; off Fremantle, 
in 6 fathoms, 1. They vary greatly in width; some may 
be 6°75 mm. long by 2°25 mm. wide, and others 5°25 mm. 
long by 175 mm. wide, and so confirm the suggestion made 
in 1906 that V. compressa, Verco, is only a variant. They 
are none of them quite so wide as the South Australian 
examples, 56 mm. by 28 mm.; and none of them quite so 
narrow, 5 mm. by 16 mm., but are intermediate. At King 
George Sound they are much more common in the shallow 
dredging than anywhere in South Australia. 
AC27 stea 
Naceila crebrestriata, Verco. 
Nacella crebrestriata, Verco, Trans. Roy. Soc. S.A., 1904, vol. geo/ 
xxvili., p. 144, pl. xxvi., figs. 20, 21; 1906, vol. xxx., p. 208; 
1907, vol. xxxi., p. 101; and 1912, vol, xxxvi., p. 183. 
King George Sound beach, 3; Yallingup, 5; Rott- 
nest Island. 2. 
bd oot Seas oseoradiata, var. nov. 
This is typically a broader and more elliptical shell, has 
about two-thirds as many radial striz, and 15 or 16 deep-pink 
axial rays, gradually increasing in width. 
This was taken at Guichen Bay, South Australia; but 
in much better condition and more abundantly at Ellensbrook 
and Yallingup. Some examples are oval rather than ellip- 
tical, being narrower anteriorly; they vary somewhat in 
width, and one has its lateral margins incurved, as though 
the narrow surface—e.g., Zostera—on which it lived had 
shrunk, and consequently had led to the contraction of the 
sides of the aperture of the shell. 
on is in my cabinet. 
-Nacella stowze, Verco. “4h a 
Nacella stoww, Verco, Trans. Roy. Soc., S.A., 1906, vol. xxx., 
pl. x., figs. 4, 5; 1912, vol. xxxvi., p. 183. 
King George Sound beach, 8; Bunbury beach, 4; Rott- 
nest Island, 2. Identical with the South Australian speci- 
mens, but in poor condition. 
Acmza patellavecta, n. sp. PI. xy., figs. 5-7 ; f, 
pl. xvi., fig. 5. i p07 So 
Shell solid, elliptical, conical. Apex at the junction of 
the anterior and middle third, eroded. Margin in profile 
concave at the sides (due to its habit of living on a patella). 
Anterior slope nearly straight, posterior somewhat conyex. 
