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TERTIARY FAUNA OF FLORIDA 



Maftra cnissiiti-ns Conr., Medial Tert., p. 69, pi. xxxix, fig. 5, 1840; Am. Journ. Sci., 



xli., p. 347, pi. 2, fig-, it, 1841. 



Mactni lii</ iii-Ira Conr., Medial Tert., p. 69, pi. xxxix., fig. 3, 1840; Proc. Acad. Nat. 

 Sci. Phila., i., p. 324, 1843. 



(S/n'sii/ii) trijfoitalis Conr., MS. 



i ivn^-i-.-ila Com-., I'mc. Acad. Nal. Sci., 1862, p. 572, 1863. 

 nsii/i-its i'l />'/</ iirlra Conr., //</</., p. 573. 

 'it^t-slii Conr., i/i/'if., p. 573. 



Chesapeake Miocene of Maryland, Virginia, the Carolinas, and of Florida 

 at Alum Bluff (upper bed), DC Leon Springs, and other localities near Talla- 

 hassee and along the Chipola River ; Pliocene of the Croatan beds, North 

 Carolina, and some localities in South Carolina. 



This well-known and variable species is of wide distribution. Short, 

 high specimens form the variety triquctra of which crassidens is a young shell. 

 Conrad, by the extraordinary carelessness which was normal to him, placed 

 the two latter names under Af/i/inia, while congcsta appears both as Ilcini- 

 t/iactrc! and as Staiidclla in different places in the same lis,t of Miocene fossils 

 printed in 1X63 ! 



Mulinia lateralis Say. 



Afactra fati-ra/ix Say, Journ. Acad. Nat. Sci. Phila., ii., p. 309, 1821. 



M<i elm roslmta Phil., Abbild. und Beschr., iii., p. 138, pi. 3, fig. 6, 1845 ; not of Spenglcr, 



1802. 

 Mtit/ni i,ir/>it/niif,-s (l)eshaycs), P. /.. S., 1854, p. 63; Reeve, Conch. Icon., Mactra, fig. 



103, 1854. 



Slniiili-l/ii liili-riilis Cinir., Pruc. Acad. Nat. Sci. Phila. 1862, p. 573, 1863. 

 Muliiica latcritlis Conr., Am. Journ. Conch., iii., Suppl., p. 31, 1868. 



Chesapeake Miocene of Duplin County, North Carolina, and the Pasca- 

 goula clays of Mississippi ; Pliocene of the Waccamaw beds of South Caro- 

 lina, the Caloosahatchie River and Shell Creek in Florida ; the Pleistocene 

 from Maine to Texas, and the recent fauna from Massachusetts Bay south- 

 ward. 



This species shows the same variations in form as the preceding. The 

 shells are smoother and less rude in the southern portion of their range, and 

 the variety i-crlm/oiitcs is relatively more abundant in the south, but may be 

 found represented wherever the species is distributed. It bears to the typical 

 form a relation analogous to that which .If. triqiictra bears to the typical M. 

 congcsta or Spisn/a Ravcucli to S. siuii/is Say. 



