TRANSACTIONS OF WAGNER 



TERTIARY FAUNA OF FLORIDA 



Family TELLINIDtE. 

 Having eliminated Saiigiiiuolaria and its allies from this family, and omit- 

 ting a discussion of the ill-known groups referred here by Conrad from 

 among his Cretaceous types, the remainder forms a very compact and natural 

 group, in which the following genera may be recognized: 



A. WITH LATERAL TEETH. 



Genus Tellina (Linne) Lamarck, 1799. Type T. virgata Linne. 



Genus Tellidora (Morch MS.) H. and A. Adams, 1856. Type T. Burnett 



Broderip and Sowerby. 

 Genus Strigilla Turton, 1822. Type T. carnaria Linne. 

 Genus Metis H. and A. Adams, 1858. Type T. Meyeri Dunker. 



B. WITHOUT LATERAL TEETH. 



Genus Gastraiia Schumacher, 1817. Type T. fragilis Linne. 



Genus Macoiiia Leach, 1819. Type (M. tenera Leach, =) T. calcarea Gmelin. 



All the above have two cardinal teeth in each valve when perfect. The 

 posterior left cardinal in Phylloda, Tellidora, and Strigilla is an extremely 

 thin lamina, attached to the anterior face of the nymphal callosity, above which 

 it rises. In opening the valves the free part of this lamina — which fits into 

 an extremely narrow chink in the right valve between the large bifid cardinal 

 and the nymph — is in Strigilla usually broken off even with the top of the 

 callosity, leaving no traces of its existence except a slight roughness which 

 disappears entirely in slightly worn valves. By careful search I have never 

 failed to find it. In Metis (alta Conr.), usually described as without laterals, 

 I have found a minute distant posterior left lateral, though in most of the 

 species there is no trace of this lamina, unless in the young shells. 



With a view of testing the constancy of the various characters which 

 have been used as a basis for sectional divisions in the Tellinid(^j I went over 

 all the recent species in the Museum and tabulated the features of each species 

 as regards lateral teeth, coalescence or freedom of the ventral part of the 

 pallial sinus, thickened radii internally, etc. The only differences found 

 throughout the family in the cardinal teeth, of which the number is invariable, 

 were those of size and in the grooving of the central cardinals. A very few 

 species after careful inspection showed no grooving, but in nearly all cases un- 

 worn specimens indicate a perceptible groove. I have been forced to the con- 

 clusion that the amount or absence of coalescence with the pallial line of the 

 ventral part of the pallial sinus is a character of minor value. Even within 



