

THE HALIOTIS, OR PEARLY EAR-SHELL. 251 
man-shell of old English writers ; ‘ Orméer’ (contracted from 
oreille-de-mer) of the French, ‘Lapa burra’ of the Portu- 
guese, ' Orecchiale’ of the Italians, and ‘ Patella reale’ of the 
Sicilians.” The Cherbourg fish-women call it, according to 
Jeffreys, "S? ieu" (six yeux), from an idea that the orifices 
in the shells are real eyelets or peep-holes. 
The shells of Haliotis are, through ignorance, frequently 
confounded with those of the Meleagrina margaritifera, or 
pearl-bearing oyster, which is the true mother-of-pearl shell, 
from which are obtained the beautiful pearls used in the 
manufacture of various articles of jewelry. The Melea- 
grine are bivalves, their shelly covering being composed of 
two pieces or valves, as is the case with the common oyster, 
scallop and clam, while the Haliotis has an univalve shell, 
complete in one piece or valve, without joint or hinge. 
The Haliotides belong to the class Gasteropoda (gaster, 
belly, pous, feet), which comprises species of Mollusks that 
are characterized by their creeping upon, or by means of a 
muscular expansion of the body, called a foot. They belong 
to the order of Scutibranchiata (scutum, a shield, branchie, 
gills), the gills, or lung, being protected by a shield of 
shelly or calcareous matter. The shells of Haliotis, how- 
ever, resemble, in general outline, the form of the human. 
far; several of the species, of which Fig. 43. 
às many as eighty are known, are rough 
externally though brilliant within. 
. The shell of Haliotis (Fig. 43) may 
be compared to a flattened Turbo, or 
top-shell, with small apex whorls and 
A disproportionately large body or basal whorl, depressed, 
largely open, and having but a slightly elevated spire, com- 
Posed of but few whorls. Again, as regards form, it holds 
the same position in comparison with Turbo that Concholepas 
| does to Purpura, Sigaretus to Natica, and to follow the anal- 
* ogies into the Geophila, Vitrina to the more closely whorled 
trochiform land species. 


