TRANSACTIONS OF WAGNER 

 012 



TERTIARY FAUNA OF FLORIDA 



and age are uncertain. Harris has described a Ceronia Singleyi (Proc. Acad. 

 Nat. Sci. Phila. for 1895, p. 52, pi. 3, fig. 3) from the Lower Claibornian of 

 Lee County, Texas, but the interior is still unknown and the generic position 

 somewhat dubious. 



Subgenus DONACILLA (Lam.) Philippi. 



lliiiiiu-illc Lam., Extr. d'un Cours., p. 107, 1812 ; Donacilla Phil. Moll. Sicil., p. 37, 1836; 

 Aiuplii<{i'vihi sp. Lam., 1818; Mcsuiii-siiui sp. Dcsh., 1830; Erycina. sp. Sby., 1822. 

 Type -I/, conicn in I'oli; Mediterranean. 



Ligament marginal, obsolete; laterals not sulcate, the anterior lateral 

 long, the posterior short, stout, triangular, with the posterior margin of the 

 cartilage-pit raised and thickened like a second tooth ; posterior ventral 

 lamina in the right valve triangular, stout, elevated, vertically directed, the 

 dorsal lamina obsolete, the anterior laminae normal. 



The group is represented in Europe, Australia, and New Zealand. The 

 shells are mostly small with a horny, often colored epidermis. The Mediter- 

 ranean species is the only member of the subfamily which displays color 

 markings on the shell not pertaining solely to the epidermis. 



Subgenus TARIA Gray. 



Taria Gray, Ann. Mag. Nat. Hist., 1853, p. 44. Mesoiii-sniti sp. Dcsh. 

 Type M. Stokcsii Gray (MS. ?) = M. latitm Desh., N. Zealand. 



Shell subtrigonal, subequilateral ; the hinge concentrated ; the laterals 

 smooth, subequal, short ; the ligament short, strong, mostly internal ; the 

 resilium narrow ; the chondrophore depressed, projecting prominently down- 

 ward ; pallial sinus well marked, sometimes deep. 



The species occur in New Zealand and on the eastern coast of South 

 America. 



Subgenus PAPHIES Lesson. 



Paphies Lesson, Dnperrcy, Voy. Coq., ii., pt. i., p. 424, 1830; .l/,jr//,,y;,r (Leach MS.) 

 Cray, DietT. N. Zeal., ii., p. 252, No. 174, 1843; M<-snifi-sin,i And. ; l',i/>/ii,i llutton, 

 Proc. Lin. Soc. N. S. Wales, x., p. 519, 1884 ; not of Lam. 



Type M. diislrafis Gmel., (= Mya iwiia-'jcltiniliii' Chcmnitx, I'aplin-s Roissyana Lesson </ 

 Mesodesma Chemnitzii Deshayes) ; New Zealand. 



Shell elongated, subequilateral, subsolenifonn, solid ; hinge concentrated, 

 heavy; laterals smooth or finely granulose, short; ligament short, mostly 

 internal, small; resilium narrow, vertical; the chondrophore. projecting ; 

 pallial sinus very small, angular. 



Two species are known, from New Zealand. 



