TRANSACTIONS OF WAGNER 

 IOIA 



TERTIARY FAUNA OF FLORIDA 



Subgenus Moerella Fischer, 1887. (+ Moera Adams, 1856, non Leach, 1815; 

 + Maera Adams, 1856, non Leach, 1813; + Donacilla Gray, 1851, non 

 Lamarck, 1812). Type Tellina donacina Linne. 



Shell small, compressed, hardly folded, acute behind, rounded in front, 

 with feeble concentric sculpture ; left laterals obsolete ; no interior radii ; the 

 sinus long, coalescent with the pallial line below. Eocene to recent seas. 



This little group is closely related to the smaller forms of Angulus, but 

 has the laterals better developed and is without internal radii. It forms the 

 transition from the forms previously considered towards Angulus. There 

 is a distinct posterior lateral in the right valve, and an obsolete anterior lateral 

 may sometimes be detected in the left valve. 



C. Hinge with a strong right anterior lateral, closely adjacent to the cardinals, 

 the left laterals absent, the posterior right lateral obsolete. 



Subgenus Angulus Megerle (em.), 1811. (-{- Fabulina Gray, 1851, + 7V/- 



linula (sp.) auct.). Type Tellina lance olata Linne. 



Shells elongated, variable in size but chiefly small, compressed, with the 

 posterior end angularly pointed and not twisted, the surface smooth or with 

 fine concentric sculpture; nymphs short and prominent, the ligament short; 

 hinge with a single adjacent lateral well developed in the right valve an- 

 teriorly; internally a thickened ray passes from the umbo just behind the 

 anterior adductor scars and one or two narrower similar rays in front of the 

 posterior adductors, often stronger in the left valve, the posterior rays some- 

 times obsolete; sinus largely or wholly coalescent with the pallial line below. 

 Eocene to recent. 



Section Angulus s. s. Surface smooth or finely concentrically striated, 



internal radii ill defined. 

 Section Scissula Dall, 1900. Surface with fine oblique grooving, not in 



harmony with the incremental lines. Type Tellina decora Say. 

 These forms constitute a well-defined and perfectly recognizable group. 



Section Oudardia Monterosato, 1885. Type Tellina coinpressa Brocchi. 

 This group differs from Angulus s. s. only in having the anterior radii 

 internally, strong and well defined. The type has oblique external grooving 

 which is wanting in other species. 



Section Peronidia Dall, 1900 (Perona>a Morch, 1853; not Perotiea 

 Curtis, 1824, nor Peronia Blainville, 1824). Type Tellina albicans 

 Gmelin (nitida auct.). 



