MANUAL OF THE MOLLUSCA. 



Family YIII. — HippUBiTn)^.* 



Genus : — HiPPimiTES. 



Sub-genus, D^ Orlignya, Woodward, 1862. 



Type, H. bi-oculatus, Lamk. ; no " ligamental inflection " of 

 tlie 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'Orhignya, but 

 presents the further peculiarity of an indefinite number of pal- 

 lial duplicatures extending all round the margin of the lower 

 valve. 



Family XL — LucEsrrD^.f 

 LoEiPES, Poli, 1791 (Jefi'reys) (see p. 456). 



Etymology, lorum, a strap ; and pes, a foot. 



Example, Tellina lactea, Linne. 



Animal with the margin of the mantle notched ; incurrent 

 tube long. 



Shell almost equilateral, cancellated, or sculptured by 

 flexuous striee; 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. Eocene . Erance. 



AxiNTJS, J. Sowerby, 1821 (see p. 431). 



Synonyms, Thysaira, &c. , Leach ; Bequania, Leach ; Crypto- 

 don, Turton ; Ptychina, Philippi ; Thiatyra, G. Sowby. ; Olau- 

 sina, Jefeeys. 



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 ; ligament 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. j See p. 455. 



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