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one or more patelliform parasites. I thought, naturally, 
they were young individuals of the same species, but they 
proved to be always examples of what I have named and 
described as Acmea patellavecta. 
Patella axiaerata, n. sp. PI. xv., figs. 3 and 4. 7 cot fee 
Shell small, depressed, conical, elliptical, apex somewhat 
antemedian, lateral margins somewhat concave, so as to be 
lifted off a flat surface. Apex blunt, surface smooth; colour 
opaque-white, numerous rays (18 in the type), golden- 
yellow, with darker golden axial hairlines in them. Margin 
simple, smooth. Spatula well marked, large, with a distinct 
neck and large head. Interior white, through which the 
yellow rays are visible. 
Dimensions. —Length, 44 mm.; breadth, 32 mm.; 
height, 1°9 mm. 
Habitat.—Type, Rottnest Island, with many others; 
King George Sound beach, 8 small. 
Variations.—Some are shorter and higher, more convex 
in the hinder slope, more acute at the apex. The number 
of golden rays may be only 12 or 10, due to the fusion of two 
narrower into a larger one; sometimes the ray, which is at 
first single, becomes later double. In some examples the 
golden hairlines in the rays are conspicuous and numerous. 
The apical region inside, for a varying extent, may be of a 
yellowish-brown colour. 
The shape of its base suggests that its usual habitat is 
the conical surface of another shell, and as this is a very 
common habit with Acmaa, it may belong to this genus. It 
recalls Patella ilibrata, Verco, by its form and apex and 
rays. It was not taken alive. 
Type is in my cabinet. 
Patella ustulata, Reeve. Dae ir bes 
Patella ustulata, Reeve, Verco, Trans. Roy. Soc., S.A., 1906, 
vol. xxx., & 206; 1907, vol. xxxi., p. 99; and 1913, vol. 
Xxxvi., p. 182. 
This was taken at Esperance Bay and King George 
Sound; at Ellensbrook up to 25 mm, long, by 20 mm. wide, 
by 7 mm. high, the largest specimen taken in the West; at 
Yallingup and at Bunbury, up to 18 mm. long.. 
They vary greatly. A common form has from 12 to 14 
broad white or yellow ribs; the rest of the shell may be white 
or yellow or black or pinkish-brown. Some, after a moderate 
growth in this fashion, become wholly black. 
They do not reach the size of those at Beachport, which 
may be 47 mm. by 40 mm. 
