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TERTIARY FAUNA OF FLORIDA 



Genus Mytilns (L.) Bolten. 



Section Alytilus s. s. Surface with chiefly concentric sculpture or smooth. 

 Type M. ediilis L. 



Section Horinomya* Morch (Cat. Yoldi, p. 53, 1853). Shell radially 

 sculptured. Type Mytilns exustus Linne. 



To these may be added : 



Subgenus Mytiloconclia Conrad. Apical region of the shell much 

 thickened and produced, with longitudinal grooves. Type M. inciwva 

 Conrad. 



The number of species of Mytilns in the Tertiary of the Eastern United 

 States is very small, but the Pacific coast pffers a larger number. 



Mytilus Conradinus Orbigny. 

 Myiilus incrassatus Conr., Am. Journ. Sci., xli., p. 347, 1841 ; Fos. Medial Tert., p. 74, 

 pi. 42, fig. 4, 1845 ; Tiiomey and Holmes, Pleioc. Fos. S. Car., p. 32, pi. 14, figs, i, 

 2, 1855 ; Harris, Bull. Pal., 3, p. 5, 1895 ; not of Deshayes, 1830. 

 Mytitus Conradinus Orbigny, Prodr. Pal., iii., p. 127, 1852. 



Mytiloco7icha incrassata Conr., Proc. Acad. Nat. Sci. Phila. for 1862, p. 291, 1862. 

 Mytiliconcha incrassata Conr., op. cit., p. 579, 1863. 



Lower Miocene of Cumberland County, at Shiloh and Jericho, New 

 Jersey, Conrad and Burns ; Miocene of the artesian well at Galveston, Texas, 

 between two thousand three hundred and eighty-four and two thousand eight 

 hundred and seventy-one feet below the surface, Singley ; Upper Miocene of 

 the Natural Well, Duplin County, North Carolina, Burns ; two and one-half 

 miles below Governor's Run, Chesapeake Bay, Maryland, Burns ; Miocene of 

 South Carolina, in the Darlington District and on the Waccamaw River, 

 Tuomey and Holmes. 



This species does not differ from the true Mytilus except in being a little 

 heavier than is usual in this genus. It has not the produced cardinal area of 

 Mytiloconclia, with imperfect specimens of which it has sometimes been con- 

 fused. 



Mytilus pandionis n. s. 

 Plate 30, Figures 9, 10. 

 Oligocene of White Beach, near Osprey, Little Sarasota Bay, west 

 Florida; Dall. 



^' Arcomytiltis Agassiz (Sowb. Min. Conch., French ed., 1840) is prior in point of time, but the 

 type has the aspect of a Septifer and the interior is not described or figured. 



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