268 MANUAL OF THE MOLLUSCA. 
FAMILY X.—HALIOTIDA. 
Shell spiral, ear-shaped or trochiform; aperture large, 
nacreous; outer lip notched or perforated. No operculum. 
Animal with a short muzzle and subulate tentacles; eyes on 
pedicels at the outer bases of the tentacles; branchial plumes 
2; mantle-margin with a posterior (anal) fold or siphon, 
occupying the slit or perforation in the shell; operculum lobe 
rudimentary ; lingual dentition similar to trochus. 
In addition to the true haliotids, we have retained in this 
group such of the trochiform shells as haye a notched or per- 
forated aperture. 
HawtoTis, L. Ear-shell. 
Etymology, halios, marine, and ous (otos), an ear. 
Type, H. tuberculata, Pl. X., Fig. 21. 
Shell ear-shaped, with a small flat spire; aperture very wide, 
iridescent; exterior striated, dull; outer angle perforated by a 
series of holes, those of the spire progressively closed. Mus- 
cular impression horse-shoe shaped, the left branch greatly 
dilated in front. In Z. éricostalis (padollus, Montfort) the shell 
is furrowed parallel with the line of perforations. 
Animal with fimbriated head-lobes; side-lobes fimbriated and 
cirrated; foot very large, rounded. Lingual teeth, median 
small; laterals single, beam-like; uncini about 70, with 
denticulated hooks, the first 4 very large. 
The haliotis abounds on the shores of the Channel Islands, 
where it is called the ormer, and is cooked after being well 
beaten to make it tender. (Hanley.) It is also eaten in Japan. 
It is said to adhere very firmly to the rocks with its large foot, 
like the limpet. The shell is much used for inlaying and other 
ornamental purposes. 
Distribution, 75 species. Britain, Canaries, Cape, India 
China, Australia, New Zealand, Pacific, California. 
Fossil, 4 species. Miocene—. Malta, &e. 
Sub-genus 2 Deridobranchus, Ehrenberg, D. argus, Red Sea. 
Shell large and thick, like haliotis, but entirely covered by the 
thick, hard, plaited mantle of the animal. 
StomATiIA (Helblin), Lamarck. 
Etymology, stoma, the aperture. 
Type, 8. phymotis, Pl. X., Fig. 22. 
Shell like haliotis, but without perforations, their place being 
occupied by a simple furrow; surface rugose, spirally ridged; 
