TRANSACTIONS OF WAGNER 

 668 



TERTIARY FAUNA OF FLORIDA 



Several species of Perna occur in the literature which do not belong to 

 the genus as 'here understood, but to Modiolus. The only other species of 

 Mdina reported from our Tertiary are the unfigured M. montana Conr. (Pac. 

 R. R. Reps., vii., p. 195, 1857), from San Buenaventura, California, of which 

 nothing seems to have been seen since it was described by Conrad, and the 

 Pcrna corndliana Harris, from the Midway stage of Alabama, near Clayton. 

 The remains of this species are quite imperfect, and it is not practicable to 

 make comparisons with M. viaxillata. 



Family PTERIID^E. 



Genus PTERIA Scopoli. 



Ptcria Scopoli, Intr. ad Hist. Nat., p. 397, 1777 ; (sole e.x. Mytihis /linim/o L.) 



Avicida Olivi, Zool. Adiiat., p. 125, 1792. 



Margaritifcra Humphrey {ex parte), Mus. Calon., p. 44, 1797 {eipud. Da Costa, 1776, 



non binom.). 

 Pinctada Bolten, Mus. Boltenianum, p. 167, 1798. 

 Avicula Lam., Prodr., p. 82, 1799. 

 Unionum Link, Beschr. Rostock Samml., p. 155, 1807. 

 Margariiiphoj-a Meg. v. Muhlf. , Entw., p. 66, 181 1. 



Melcagrina Lam., Extr. d'uii Cours, p. 104, 1812 ; An. s. Vert., vi., i, p. 150, 1819. 

 Margarita Leach, Zool. Misc., i., p. 107, 1814; Swainson, Zool. 111., 2d Ser., ii,, pi. 55, 



1831 ; not of Leach, 1819, or of Lea, 1838. 

 Per/aumfer Schnm., Essai, p. 107, + Avieula, p. 136, 1817. 

 Anonica Oken, Handb. d. Zool., 1815 ; Naturg. fiir Schulen, p. 652, 1821. 



The present group was called Margaritifera by J. Woodward in 1728, a 

 name long antedating Klein's Avicula, but not introduced into binomial no- 

 menclature until after the publication of Pteria by Scopoli. The Tertiary and 

 recent forms include the following subgenera : 



Pteria s. s. Type Myiihis hiriindo Linne. 



Margaritifera Humphrey. Type M. margariferus Linne. 



Electroma Stoliczka. Type Avicula siiiaragdina Reeve. 



Of these the latter may be represented in the recent fauna of the Antilles 

 by Avicula Candeana Orb., which seems to owe its characters to commensalism 

 with sponges ; Margaritifera is represented by the Antillean pearl-oyster, 

 M. radiata Leach, but, curiously enough, neither is known as an American 

 Tertiary fossil. 



Of typical Ptcria there are but few in our Tertiary, and these are often 



