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TKRTIAKY KAUNA OF FLORIDA ' " 



Miocene of Maryland; of Duplin County, North Carolina; Shiloh, New 

 Jersey ; and Alaska ; Pliocene of the Caloosahatchie beds, Florida, and of 

 the California coast at San Pedro and Santa Barbara; Pleistocene of northern 

 North America and Kurope; recent, almost universally distributed in the 

 temperate and colder seas. 



Sa.vicava abntpta Conrad (Pac. R. R. Reps., v., p. 324, pi. 3, figs. 25, 25 a, 

 1856), from the Pleistocene of San Pedro, California, is indeterminable, but 

 probably not a Saxicava ; the same may be said of S. parilis Conr. (Am. 

 Journ. Conch., ii., p. 70, pi. 4, fig. 6, 1866), from the Miocene marl of Shiloh, 

 New Jersey. S. pcctorosa Conr. (1834, Medial Tert., p. 18, pi. 10, fig. 3, 

 1838), from the Miocene of Virginia, is probably a Petricola, as is 6". legitmcn 

 Deshayes, from the Pleistocene of San Pedro, California. The latter may 

 be identical with P. canlitoidcs Conr. 5. myaformis Cotu. (Am. Journ. Conch., 

 ii., p. 70, pi. 4, fig. 6, 1866) is a Thracia. S. lancea H. C. Lea (1845) > s n t a 

 Saxicara, but belongs in a group closely related to, or the same as, Sportella. 

 The genus Saxicavella Fischer (Arciiiclla Phil., 1844, not Oken, 1815, nor 

 Schum., 1817), founded on the little Mya plicata Montagu, though present in 

 the European Pliocene, has not been detected in America. 



Genus CYRTODARIA Dauilin. 



I'vi-ttH/iiin- Pamlin, IJull. Soc. Philom., xxii., p. 170, 1799. 

 I'vrtiiilaria Keuss, Kepertor. Coinin., p. 351, 1800. 

 (//)( inicris Lam., An. s. Vert., v., p. 457, 1818; not Lam., 1799. 

 (/'/n i/iii'ra Hlainv. Malac., p. 571, pi. 80, tig. 3, 1825. 



Type Cyrtodaria siliqita Dauilin. 



Cyrtodaria siliqua Dauclin. 



(_'. silit/iia Dauilin, t'p. cit., 1799. 



Mya silit/im Clicmn., Conch. Cab., xi., p. 192, pi. 198, fig. 1934, 1795. 



(i'h'i'iiiit->is iiitTitssitta Lam., Syst. An. s. Vert., p. 126, 1801. 



Mya f>it'i'a \Vmxl, ('.en. Conch., p. 96, pi. 22, fig. 5, 1815. 



Pleistocene of the Arctic and boreal Atlantic coasts ; recent from Cape 

 Coil northward to the Arctic coast, and west on the Arctic coast to the mouth 

 of the Mackenzie River ; Richardson. 



This well-known shell does not seem to have penetrated to the region of 

 Bering Strait, and is only represented in Bering Sea by a diminutive recent 



analogue, the C. Knniana Dunker. 



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