Pre/ace. Xl 



sodiis, Matthew ; No. 54, Oniitholestes, Osborn ; No. 

 55, Neohipparion, Gidley ; No. 57, Glyptotherimn, Os- 

 born ; No. 58, Parmnylodon, Brown ; No. 60, Triccra- 

 tops, Lull ; No. 61, Crcosaiums, Osborn. 



Papers especially relating to philosopJiical anatoniy 

 are those on the teeth and feet by Osborn and Wort- 

 man and Gidley and especially No. 39, DolicJioccphaly 

 and Brachycephaly, by Osborn and No. 52, The Ele- 

 phants Skull, by Gregory. 



Faunal Lists of Different Horizons. — We 

 have also attempted to give complete faunal lists of 

 different horizons. The most comprehensive paper of 

 this character is No. 28, by Matthew, including faunal 

 lists of the entire Freshiuater Tertiaries of the West. 

 Other papers are No. 12, Puerco jMauinials, Osborn 

 and Earle ; No. 21, Puerco jMauiinals, by Matthew; 

 No. 47, Pleistocene Fauna from Hay Springs, by Mat- 

 thew ; No. 50, Lower Oligocene Fauna of the Pipestone 

 Springs, by Matthew ; No. 59, Miocene Fauna of 

 Northzuestern Texas, by Gidley. 



Memoirs on Fossil Mammals. — These include 

 The Extinct Rhinoceroses, Part I, by Osborn, and Fossil 

 Mammals of the Tertiary of Northeastern Colorado, by 

 Matthew. The memoir on the Rhinoceroses will be 

 continued and the memoir on the Evolution of the 

 Horse is in preparation by Osborn with the coopera- 

 tion of Mr. J. W. Gidley. 



PHOTOGRAPHY. 



Field Photographs. — In connection with the var- 

 ious expeditions enumerated on page iii a series of 

 580 field photographs have been taken, the negatives of 

 which are filed in the department for use in connection 



