Article III.— A PROVISIONAL CLASSIFICATION OF 

 THE FRESH-WATER TERTIARY OF THE WEST. 



By W. D. Matthew, 



The table of formations immediately following was drawn up 

 by the writer under the guidance of Prof. Osborn and Dr. Wort- 

 man, for the arrangement of the collections in the American 

 Museum of Natural History, and submitted to the late Prof. Cope 

 and to Prof. W. B. Scott for approval or amendment. The faunal 

 lists appended are made up chiefly from the study of these collec- 

 tions, covering all the formations of the Western Lakes except 

 the Pliocene horizons. A partial essay is made at a critical 

 revision of the species ; characteristic and well marked species 

 are in special type, and those considered invalid are in roman. 

 It is quite impossible to make this revision with any approach to 

 completeness, from the fragmentary character of many types and 

 the meagreness of descriptions. The object of the lists is to 

 assist in the correlation and classification of the various basins by 

 showing the characteristic fauna. The exact horizon and locality 

 are therefore given as fully as possible ; and to facilitate future 

 comparison of species, the location of each type specimen is given, 

 as far as known to the writer. No bibliography or complete 

 synonymy of the species is included ; it would be undesirable in 

 this connection, as well as rendered superfluous by the excellent 

 bibliography of mammals recently published by Prof. Trouessart. 



In this preliminary attempt, errors will doubtless be numerous. 

 The writer will be glad to have his attention called to any, that 

 they may be corrected in a subsequent edition. The synonymy 

 of genera and species is necessarily to a considerable extent pro- 

 visional, and will require revision, especially in the Creodonta 

 and Primates. Some of the results of Dr. Wortman's recent 

 studies on the former group are embodied here. 



New genera defined in this list : Palceictops, p. 35; F/ihwcyon, 

 p. 54 ; Miolabi Hay, p. 74, 



New species defined : Palaolagus intermedins, P- 53 ; Phlao- 

 cyon leucosteus, p. 54 ; Ictops hii'latus, p. 55 ; Aceratherium pro- 

 fee turn, p. 71. 



The following names not heretofore used will be defined in 



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