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789 



TERTIARY FAUNA OF FLORIDA 



Mytilus (Hormomya) hamatus Say. 

 ? My/i/iis rccimnis Kai., Mon. Coq. Biv. Ohio, p. 55, 1820; New Orleans. 

 Mytilus haiiiatus Say, Journ. Acad. Nat. Sci. Phila., ii., p. 265, 1822 ; Binncy's reprint of 



Say, pp. 91, 204, pi. 50; Dall, Bull. U. S. Nat. Miis. No. 37, p. 38, 1889. 

 Bracliydontcs hamatus Perkins, Proc. Bost. Soc. Nat. Hist., .\iii., p. 156, 1869. 

 ? Dft'isscna rcciiri'a Fischer, Journ. de Conchyl., vii., p. 130, 1S58. 

 JMytilliis striatiis Barnes, Am. Journ. Sci., vi., p. 364, 1823 ; Say, Am. Conch., v., pi. 50, 



1832. 

 iSIodiola /laiiiatus Verrill, Am. Journ. Sci., 3d Ser., iii., p. 211, pi. 7, fig. 3, 1872 ; Inv. 



An. Vineyard Sound, p. ^93, 1873. 

 Mytilus caroliiicnsis Conrad, Journ. Acad. Nat. Sci. Phila., vii., p. 244, pi. 20, fig. 6, 



1837; Tryon, Am. Mar. Conch., p. 187, fig. 513, 1874. 



Pliocene of the Caloosahatchie, Dall ; Pleistocene of Wailes Bluff, St. 

 Mary's County, Maryland, Burns ; recent from Long Island Sound south to 

 Costa Rica. 



On the Pacific coast, besides M. ediilis, the Pleistocene affords the great 

 M. californiamis Conrad, which even, according to Cooper, is found in the 

 Pliocene, and M. pedroamis Conrad, which is perhaps identical with M. edulis. 

 The Pliocene affords M. Middciidorfii Grewingk (Beitr. Kenntn. N. W. Kuste 

 Am., p. 360, pi. vii., figs. 3 a-c, 1850) and M. Condoni Dall (Nautilus, iv., p. 87, 

 Dec, 1890), peculiar species with a few broad plications posteriorly, from 

 Alaska and Oregon respectively. In the Miocene are the large M. Mathezu- 

 soni Gabb and the M. inczensis of Conrad, which may prove to be the same 

 as Modiola imtltiradiata Gabb ; both are radiately sculptured and of rather 

 uncertain outline. In the Eocene (Tejon) are M. ascia Gabb and M. himerus 

 Conrad, both rather obscure, smooth species, and M. {Hormoviyd) dichotoimis 

 Cooper (Bull. Cal. State Mining Bureau, No. 4, p. 49, pi. v., fig. 64, 1894), of 

 which the characters, even the genus, are imperfectly known. Its relations to 

 Septifcr dicliotoinus Gabb and 5. bifiircatiis Reeve, as well as Mytilus bifiircatus 

 (Conr.) Stearns, remain to be clearly made out. 



Subgenus MYTILOCONCHA Conrad. 



Myoco7icha Conrad, Medial Tert., p. 52, 1840. 



Mytiloconcha Conrad, Proc. Acad. Nat. Sci. Phila. for 1862, p. 290, 1862. 



Mytiliconcha Conrad, op. cit., p. 578, 1863. 



Mytilus (Mytiloconcha) incurvus Conrad. 

 Myoconcha incuma Conrad, Medial Tert., No. I, p. 3 of cover, 1839; No. 2, p. 52, pi. 

 28, fig. I, 1840. 



