TRANSACTIONS OF WAGNER 

 726 



TERTIARY FAUNA OF FLORIDA 



Pecten principoides Emmons, Geol. N. Car., p. 280, fig. 198, 1858. 



I'cctcn cliiitoncnsis Meek, S. I. Check!. Mioc. Fos., p. 5, 1864. 



Chlamys (Placopecten) Clintoniiis Verrill, Trans. Conn. Acad., x., p. 78, 1897, in part. 



Pccti 'a fii'inccps Verrill, op. cit., in syn., non Kmmons. 



Pectcn .}[ullcri Verrill, op. cit., in syn., not of Dall. 



Miocene of Coggins Point, Grove Wharf, York River, and James River, 

 Virginia, Rogers, Conrad, Lea, and Harris; and of Maryland, Dr. Foreman; 

 and of North Carolina at Murfreesboro, Meherrin River, Emmons. 



This remarkable shell appears to be quite limited in its range, and is only 

 known in the Miocene of Maryland, Virginia, and North Carolina. It presents 

 at a first glance a remarkable resemblance to the recent Pecten magdlaniais 

 (Ch.) Gmelin, which is doubtless its descendant. The latter can, however, be 

 at once discriminated from the fossil by the shorter hinge-line, higher auricles, 

 much narrower resiliary pit, and, usually, the smaller and less central adductor 

 scar of the recent shell. A very large series of both recent and fossil speci- 

 mens which I have carefully studied confirms the uniformity of the above- 

 mentioned characters. As a rule the radiating threads in the fossil are 

 markedly coarser than those of the living species. In both the byssal notch 

 of the adult is represented by a shallow sinuation, and the ctenolium, present 

 in the immature stages, is usually buried in shelly matter in the adult. 



Since so much confusion has occurred between these two species, a state- 

 ment of the synonymy of the living form may be useful. 



Pecten (Placopecten) magellanicus Gmelin. 

 Amusiiiin iini^nitin inagellanicnm, etc., Chemnitz, Conchy!. Cab., vii., p. 290, pi. 62, fig. 



597, 1784; Schroter, Einl. Conch., iii., p. 323, 1786; Favanne, pi. 55, fig. e, 2. 

 Ostrca ma^ellanica Gmelin, Syst. Nat., vi., p. 3317, 1792 (not 1788, as frequently quoted) ; 



Dillwyn, Descr. Cat. Rec. Sh., i., p. 250, 1817. 

 Ostrca grandis Solander, Portland Cat., 1786 (fide Humphrey). 

 Pecten graniUs Humphrey, Mus. Cal., p. 51, No. 969, 1797. 

 ? Amiisiiuii Icstitdiiiarhtm liolten, Mus. Holt., p. 165 (name only), 1798 ; 2" Ausg., p. i 15, 



1819. 

 Pecten nta^elltinicits Lam., An. s. Vert., vi., p. 165, 1819 ; ed. Dcsh., vii., p. 134, 1834 ; 



Gould, Inv. Mass., p. 132, 1842; eel. Kinney, p. 196, fig. 494, 1870; Conr., Am. 



Mar. Conch., i., p. 6, pi. i., fig. i, 1831 ; Sim., Sh. N. Kngl., p. 8, 1851. 

 Pecten fitscus Linsley, Am. Journ. Sci., 1st Ser., xlviii., p. 278, 1845 (name only); Gould, 



Am. Journ. Sci., 2d Ser., vi., p. 235, fig. 6, 1848; Stm., Sh. X. Kngl., p. 8, 1851. 



(Young shell.) 

 Peeten ln-iinneiix, Stm., Sh. N. Engl., p. 58, in errata, 1851. (Young.) 



