215 
curved, and in having much finer and more crowded strix. It 
differs from 4. subunduiata, Angas, in being less elevated, 
less orbicular, with a sharper and more antecurved apex, and 
in its colour. 
Ix O7TO Acmea septiformis, Quoy and Gaimard. PZ 
Patelloida septiformis, Quoy and Gaimard, Voy. Astrolabe, 
Zool., 1834, vol. iii., p. 862, pl. Ixxi., figs. 43, 44; Lamarck, Anim. 
8. Vert. (2nd edition, Deshayes, etc.), 1836, vol. vil., p, 550; 
Lectura septiformis, @. and G., Angas, Proc. Zool. Soc., Lond., 
1867, p. 220, No. 219; Acmea septiformis, Q. and G., Ten.-Woods, 
Proc. Roy. Soc., Tasm., 1877, p. 50; Pilsbry., Tryon, Man. Conch., 
vol. xiii., 1891, p. 55, pl. xxxvii., figs. 98, 94; Adcock, Handlist 
Aquatic Moll. 8. Aust., 1893, p. 9, No. 397; Tate and May, Proc. 
Linn. Soc., N.S.W., 1901, vol. xxvi., p. 412; Pritchard and Gat- 
liff, Proc. Roy. Soc., Vict., 1903, vol. xv. (n. s.), pt. 2, p. 195. 
A. scabrilirata, Angas, Proc. Zool. Soc., 1865, p. 154, and p. 
186, No. 201; Pilsbry., Tryon, Man. Conch., 1891, vol. xiii. p. 
56; Pritchard and Gatliff, lot. cié. 
A. petterdi, Ten.-Woods, Proc. Hove Soc., Tasm., 1877, p. 
155; Pilsbry., op. cit., p. 54; Tate and May, loc. cit.; Pritchar 
and Gatliff, loc. cit. 
Obs.—Tate and May say 4. petterdi is the senile form. 
The shell varies in altitude from 18 mm. long, and 4°5 
mim. high, to 14 mm. long and 6 mm. high. Some have a 
cap occupying up to one-third or one-fourth of their size, with 
comparatively steep sides, with an abrupt assumption of the 
ordinary depressed shape, looking like one aemaea mounted on 
another. ‘The base is in some uneven, resting on the front 
and back edges possibly because their roost was not flat. The 
radial lire may be marked from apex to base, and numer- 
ous, or very few, or absent, even when not rolled or eroded. 
The surface may be uniformly horn-coloured, or white, with 
radial black-brown widening bands, or with reticulated or 
roundish tessellated markings, The inner margin may be 
articulated brown and white, or have a uniform brown mar- 
gin or be wholly white. The interior may be whitish, 
opaque glistening white, bluish-white, or with the outer col- 
our showing through. The spatula may be dark chestnut- 
brown and very distinct, or almost invisible. 
The surface is generally in very good condition, but some 
are markedly pitted with round shallow holes, especially about 
the summit, evidently due to boring by molluscs, and not to 
erosion. 
Locality.—From Port MacDonnell to Fowler’s Bay ; 
rather common. 
Acmcaeatitharus, Rew fro bally th, 
Patella cantharus, Reeve, Conch. Icon., vol. viii., 1858/ pl. 
xl., f. 181; Pritchard and Gatliff, Proc. Roy. Soc., Vict., 1908, 
NE ee ee ee ee ee 
ee 
ee siamnsearaersnerares 
—— 


