211 
tude varies very greatly from 3°5 mm. in a shell 17 mm. 
long to 8°5 mm. in one 18 mm. long. When on the rocks they 
may be so rough and acutely costate as to be mistaken for 4. 
alticostata, Angas. Usually with a flat base, it may rest on 
its ends, with the sides of the border much raised. As vari- 
ations from the description by Ten.-Woods, the spatula may 
be white, with some brown clouding in its centre, the interior 
of the shell being a light brown,.or the spatula may, be black 
and-the rest of the interior white except. for black articula- 
tions of the border. The most constant feature in the orna- 
ment is the dark dotting of the spatula, but in the pallid 
examples this is very slight. 
Adcock makes P. gealei, Angas, a synonym, and Pritch- 
ard and Gatliff give it priority, and A. marmorata as a 
synonym ; but’ Angas’s shell is a distinct species. P. latistri- 
gata, Angas, from Aldinga, is a half-grown example, with 
broad radial stripes. 
Acmzea calamus, Crosse and Iischer. 
Patella calamus, Crs. and F., Journ. de Conch., 1864, p. 
348; 1865, p. 42, pl. iii., figs. 7, 8; Tate and May, Proc. Linn. 
Soc., N.S.W., 1901, vol. xxvi., pt. 3, p. 412; Acmea calamus, Crs. 
and F., Angas, Proc. Zool. Soc., Lond., 1865, p. 186, No. 200; 
Pilsbry., Tryon, Man. Conch., 1891, vol. xui., p. 54, pl. xxxvii., 
fies. 3, 4; Adcock, Handlist Aquatic Moll., S. Aust., 1893, p. 9, 
No. 395; Pritchard and Gatliff, Proc. Roy. Soc., Vict., 1903, vol. 
VEC ITHES 8) SD UE DELO (in 
Locality of type, St. Vincent Gulf, South Australia. I 
have taken it at Port MacDonnell, and dredged it from Back- 
stairs Passage to Spencer Gulf, alive, at all depths from 5 to 
17 fathoms. Most abundant in the shallower water. 
Tate in Trans. Roy. Soc., 8. Aust., May, 1897, thought 
it would prove to be a synonym of dcmwa conoidea, Quoy 
and Gaimard, and this suspicion seems to have been con- 
firmed, as he lists it thus in his Tasmanian Census in 1901. 
He speaks of A. conoidea, in 1897, as though he had seen 
Quoy’s type, and as having a circular aperture and five 
radial threads. But Quoy seems to have only had one shell 
collected at King George’s Sound. This Deshayes had not 
seen (Anim. 8. Vert., 2nd edit., vol. vil., p. 551), and Quoy 
does not describe it as having any radial threads, but.as being 
“obtuse and rounded at the apex”; this 4. calamus never is, 
either alive or dead or rolled. © 
The dimensions given by Crosse are 125 mm. by 10 by 6, 
but they reach 165 by 14 by 7-5. The shell may be wholly 
white within and without, or the apical part may be white 
and the rest ornamented,. either with tiny brown spots, more 
or less abundantly and irregularly scattered over the surface, 
