180 UNIVALVES——HALIOTIS. 
three to seven are generally open, and the others per- 
fectly closed. The H. parva is remarkable for the large 
elevated rib or angle on its back. 
The second division consists of the imperforated spe- 
cies. The H. imperforata, which has an ovate form, 
with an exserted spire, and prickly ribs, is a charac- 
teristic specimen. 
The species which may be noticed as rarieties of the 
genus are the H. pulcherrima, H. glabra, H. australis, 
H. parva, H. imperforata, and H. impertusa. 
The Haliotides are found on the shores of Europe, 
Africa, and India, where, like the Limpets, they adhere 
to the rocks, from which they are with difficulty removed. 
The name of the genus is derived from adAc wra sed= 
ears, in reference to the habitat and form of the shell. 
Diviston 1.—Shell perforated. 
Famity 1.—Rouwndish or ovate. 
Scientific Name. Locality. Common Name. 
Midze --+++++-+-- East Indies, Mauritius, 
Cape of Good Hope - Midas’ Ear 
Pulcherrima -- --- King George’s Sound -- Beautiful -- do -- 
Virginea ------.- New Zealand ----+----- Iridescent - do - 
Tuberculata ---- Europe, West Indies ---- Common -- do -- 
Striata-----..-+.. Asiatic Ocean, Barbary - Wrinkled - do -- 
Bistriata -------- Africa +e+++.e. se ee sees Double-lined do - - 
Varia +--+ +++: Last Indies --+++++++--- Rough-striated do 
Marmorata------ Africa, East Indies ----- Marbled -- do -- 
Glabra -+ «+--+. South Seas .--+---.-+--- Smooth mottled 
Australis «+--+. New Zealand ----+.-- -» Rough plaited do 
Gigantea eeeeee N. Holland, N. S. Wales Gigantic -- do -- 
| filha oe bad - New Zealan dre «te vterom <fels Tris .--+-s- do --« 
Cracherodii --.-. California --..+.... ++++ Cracherode’s do 
