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ANAXYSIS 0? THE ?AU1:A. 

 1. Biolopi ^al Anals"si:5. 



DuriiTgr the coiirce of the present Btiidj/ 3 9S upeoies 

 and varietieG ^'^ p-'-lf^ey -^'-'^n t "ve oe en recop^xi,.^-.., -heee are 

 segregated into G4 genera atiu 40 families. 7ine of the speo- 

 iec are indeterrninaTDle and 83 are ne'Wi Perhaps .. ' .gle 

 locality? of the reLativel;/ v/ell-Tmovm Tertiary- deposits of the 

 Coastal Plain province of the Ur.ited States has yielded a 

 bivalve fauija of such extensive proportions, although the 

 /^liocene marls "-^^serl along the 3aloosahatehie P.iver in 

 Florida have furnished an equal lumloer of species and the 

 entire oelecypodan asoemhlage of that fauna and also of the 

 I'.Iiocene '"orlctown fauiia is greater. To other explored loealitj^ 

 in the Antillean region has revealed oji equally prolific fauiia, 

 but it must be remembered that, strictly :3pesfein?r, the paleon- 

 tolo'-'ic investigation of that irit'.iei.- oiiii: cuta htis but begun. 

 It is fortuimte indeed that oonoitions of '_ mentation during 



the deposition of the 3ov.-den beds and siibsenuent events were 

 of such a nature as to furnish an optirium .uetting for the revel- 

 ation of the character, of an Antillean raid-Tertiary niolluscan 

 faui.a. 



The Prionodesmacea play a siirotisingly importaiit role, 

 being represented by 79 species, more than 40 per.exit of the 

 entire fauioa. The tasodonts, vath 44 species, are larp-ely' 



