FREE INSTITUTE OF SCIENCE 



837 



TERTIARY FAUNA OF FLORIDA ^' 



ences they are included in the above synonymy. The original publication of 

 Bruguiere's name is to be found on Plate 230 of the Encyclopedie Methodique, 

 and not in the earlier printed table of genera. There is, of course, no diag- 

 nosis ; no species are named, and no references given ; merely the name at 

 the top of the plate, upon which the shells figured are not all Corbulas. 

 Authors who accept a name on such a basis have no right, logically, to take 

 exception to any of Bolten's names. Lamarck cited no example in the Pro- 

 drome, and the list of specific names in the Systeme, beginning with C. sulcata, 

 appears to be the first occasion when the requirements of nomenclature were 

 complied with. No type was cited even at that time, or for much later, and, 

 curiously enough, the shell figured by Bowdich to illustrate the genus in 1822 

 is probably not a Corbula. Megerle's name was the first applied to C. sulcata 

 exclusively, and must be retained for the seclion of the genus typified by that 

 species. The typical section of Corbula will necessarily be reserved for some 

 one of the other forms included in the list of iSoi, which are also figured on 

 the above-mentioned plate. This leaves only a choice between C. niargaritacea 

 and C. gallica Lam., and, as the former seems to be some kind of an Atiatina, 

 we are obliged to fall back upon C. gallica as the type of Corbula in the 

 stricter sense. This agrees with the arrangement of Nyst, whose first species 

 of true Corbula, after segregating Corbulomya, is C. gallica. The C. sulcata 

 group is not sharply separated from the typical Corbula, and the peripheral 

 species merge. 



Azara and Poiauioniya are exact synonyms of Erodoiia. Corbulomya is 

 identical with the earlier Lentidimn. Gray has contributed a group of nomina 

 niida, based on undescribed species supposed to be Carbides. An error of 

 Gray, by which Agina Turton (based on Saxicava arcticci) was referred to 

 the Corbulidce, has been widely copied. The supposed type, Corbula gibba 

 Olivi, is a true Co7-bula. A group of very remarkable and very variable 

 brackish-water Pliocene species is comprised under the name of AjiisotJiyris 

 Conrad (-f- Pachydon Gabb). The other names stand for fairly distinct 

 sections of the genus. 



The following arrangement of the group is proposed : 



Genus CORBULA senso lato. 

 Valves unequal, the right usually larger, both more or less rostrate ; 

 hinge of (in the right valve) a single large tooth below the beak with a deep 

 resiliary pit behind it and no lateral laminae ; the left valve without laterals, 



