MANUAL OF THE MOLLUSCA. 
Famity VIIJ.—H1pruririp2.* 
Genus :—HIPPURITES. 
Sub-genus, D’ Orbignya, Woodward, 1862. 
Type, H. bi-oculatus, Lamk. ; no ‘‘ ligamental inflection ”’ of 
the outer shell. 
Fossil, 4 species. Middle Chalk. Europe. 
Barrettia, Woodward, 1862, dedicated to Mr. Lucas Barrett, 
late Director of the Geological Survey of the West Indies. 
Type, B. monilifera, Woodward. ‘‘ Hippurite Limestone.” 
Jamaica. No ‘‘ligamental inflection” as in D’Orbignya, but 
presents the further peculiarity of an indefinite number of pal- 
hal duplicatures extending all round the margin of the lower 
valve. 
FAMILY XI.—LuUcINIDa.t 
Loripss, Poli, 1791 (Jeffreys) (see p. 456). 
Etymology, lorum, a strap; and pes, a foot. 
Example, Tellina lactea, Linné. 
Animal with the margin of the mantle notched ; incurrent 
tube long. 
_ Shell almost equilateral, cancellated, or sculptured by 
flexuous strie; lunule short; cartilage quite internal; teeth, 
one cardinal in the right, and two in the left valve; laterals 
remote, and sometimes indistinct. 
Distribution, species. Atlantic, Mediterranean, West Indies. 
Fossil, species. Hocene . Hrance. 
Axtinus, J. Sowerby, 1821 (see p. 431). 
Synonyms, Thysaira, &c., Leach; Bequania, Leach; Crypto- 
don, Turton; Ptychina, Philippi; Thiatyra, G. Sowby.; Clau- 
sina, Jeffreys. - 
Example, Tellina flexuosa, Montagu. 
Animal with the mantle margin thickened, open, not pro- 
longed into tubes; foot long, sub-cylindrical, and very slender. 
Shell globular, posterior side furrowed or angulated, umbones 
much recurved; lunule short or indistinct; hgament usually 
and to a certain extent external, placed in a groove on the hinge 
line, and outside the hinge-plate; teeth altogether wanting. 
In A. flexuosus, the hinge-plate is indented in the right valve 
immediately below the beaks, and slightly reflected in the left, 
* See p. 440. { See p. 455. 
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