7o8 JAMES H. GARDNER 



In the last paragraph of the above quotation of Cope's description, 

 he states that the "Puerco marls" do not appear to represent the Fort 

 Union or "Lignite beds of the North"; in writing later on the sub- 

 ject for the Geographical Survey west of the One Hundredth Meridian 

 (Annual Report [1877], Part II, p. 18) he remarks that these 

 beds "may represent the Fort Union or Lignite beds of the Upper 

 MissoViri some of whose strata they resemble in color and consistence." 

 These remarks are noted with interest since recent explorations have 

 shown that Torrejon fossils, which characterize the upper part of 

 Cope's original Puerco, do occur in the Fort Union beds of Mon- 

 tana. s^'^^ Cope states that he did not succeed in obtaining fossil 

 remains from the Puerco, other than petrified wood, and mentions 

 finding numerous fragments of silicified limbs and trunks of dicotyle- 

 donous and palm trees, among them one stump which measured five 

 feet in diameter. (See Fig. 7, this paper.) These remains are indeed 

 abundant in this vicinity; on the summit of the mesa two miles west 

 of Cuba post-office, which is the village Nacimiento, there are some 

 ancient Stone ruins which were built in large part of specimens of 

 silicified wood. 



Although Cope was unable to find satisfactory fossils in the Puerco 

 at the time of its discovery in 1874, he obtained in 1880 the services 

 of an experienced collector, David Baldwin, of Farmington, New 

 Mexico, to make careful search for vertebrate remains in that forma- 

 tion. Baldwin collected with great success at intervals for several 

 years, evidently finding the first Puerco fossils in the vicinity of Naci- 

 miento and northward where the formation was known to Cope. 

 More than ninety species of fossil mammals were sent from the Puerco 

 which were described by Cope between 1881 and 1888 in numerous 

 papers presented to the American Philosophical Society, Philadelphia 

 Academy of Science, and the American Naturalist. These papers 

 were devoted exclusively to descriptions of the fossils, with the excep- 

 tion of a brief note on "The Relation of the Puerco and Laramie 

 Deposits" in the American Geologist for October, 1885, here quoted 

 from as follows : 



Some writers having suspected the identity of the formations above named, 

 and the consequence which follows, that the Puerco mammahan fauna was con- 

 temporary with the dinosaurian fauna of the Laramie age, the following observa- 

 tions on their stratigraphic relations are now given. They are derived from the 



