TRANSACTIONS OF WAGNER 

 606 



TERTIARY FAUNA OF FLORIDA 



represented in the Eocene by several small, degenerate forms which have no 

 descendants. They are : 



T. ellipsis Lea (Contr. Geol., fig. 56). A good species, not identical with Pectun- 

 culns perplamts Conr. 



T. perplana Conrad (Hmopsis pcrplanatiis d'Orb.). Very like decliiis, but 

 more rhomboidal and more flat. It is much larger than T. ellipsis. 



T. corbuloides Conrad. This species has never been sufficiently described and 

 is unfigured. By some blunder a specimen of T. dcdiiis has been 

 mounted as the type of corbuloides in the collection of the Academy 

 of Natural Sciences. The descriptions, however, show that this specimen 

 cannot be the original type. If it were, the name dcclivis should be 

 adopted. 



T. decisa (Conrad?). The original dccisa is represented in the Academy's 

 collection by a specimen of Trinacria pcctiincnlaris Lea, but this does not 

 agree well with Conrad's figure and brief description. Mr. T. H. Aldrich 

 has obtained some specimens of a Claiborne Trigoiwarca which agrees 

 much better with Conrad's figure, and is probably the species he had in 

 mind. It appears to be distinct from the others. 



T. dedivis Conrad. This is the largest Claiborne species and agrees well with 

 Conrad's figure (Journ. Acad. Nat. Sci., 2d Ser., iv., pi. 47, fig. 13) and 

 original description. It appears to be rare. It is not a Trinacria nor is 

 it the same as Pectnnadus minor, as asserted by Conrad and others. It 

 has been collected at Wahtubbee as well as at Claiborne. 

 The following species belong to Glycymeris ( Pcctitncnlns} proper : 



G. trigonella Conrad (+ P. dcltoidcus Lea). This is very common at Claiborne 

 and varies from trigonal to rounded, and from smooth to radiately ribbed. 

 As the specimens intergrade completely, the mutations can hardly be 

 named varieties. Conrad's name was first printed (Am. Journ. Sci., xxiii., 

 p. 342, Jan., 1833), though he did not figure the species. 



G. minor Lea (fig. 54). This species appears to me distinct from G. trigonella. 

 to which it is most nearly allied. It differs in shape, is a thinner, wider, 

 and more compressed shell. It reaches a length of nine millimetres, and 

 the inner basal margins are sharply crenulated. Conrad's reference of it 

 to T. dedivis, as a synonym, is obviously erroneous. 



