Kansas, Oklahoma, New Mexico and Texas. 207 



younger; but it was impossible for me to go to Monte 

 Revuelto, or any other part of the Tucumcari region, to ex- 

 plore that upper series, and consequently I cannot be respon- 

 sible for not having found at the Tucumcari region the Lower 

 Cretaceous or Neocomian. It is very unjust to attack me in 

 regard to the age of strata which I have not seen, and above 

 all it is highly erroneous to deny the existence of the Jura at 

 the Tucumcari region. My adversaries have made use of the 

 anti-stratigraphic method of placing in a single list all the 

 fossils they got there, without any regard to their relative posi- 

 tions in the strata. This placing in a single mass all the fossils 

 of the Tucumcari region is not the way to make exact observa- 

 tions. I protest loudly against such a procedure. For it is 

 easy to see the special purpose in view, viz : to show Creta- 

 ceous species mixed with Jurassic ones, and to conclude that 

 the Jura did not exist there. It is contrary to careful strati- 

 graphy to do so, and very unfair. Each group and even each 

 bed should be given with the list of fossils found in each, 

 otherwise lists of fossils all together are deceptive, and cannot 

 be accepted as paleontological proof of the age of all the strata 

 of a whole region. That the Lower Cretaceous exists at the 

 Tucumcari region I am ready to believe, but the beds belong- 

 ing to it are all above those which I have classified as Jurassic. 

 In conclusion, I have to say that in the paper of Mr. Hill we 

 have another example of erroneous determination of a Gryphwa 

 which has led some geologists to continue their disbelief in 

 the existence of the Jura at the Tucumcari. The Tucumcari 

 region is open to every observer, and I am fully confident of 

 the final verdict. 



Tabular view of the strata of the Tucumcari region. 



Cretaceous strata of Monte Revuelto, six miles east of 

 Pyramid Mount. Thickness about 200 feet. The con- 

 o tact bed with the Jurassic formation has not yet been 



§ <{ described. 



Nota bene. — Very likely a discordance of some sort exists 

 at the contact of the Jura and Cretaceous. 



{ Jurassic strata existing above the top bed of the Pyramid 



j Mount section. Thickness unknown. 



£ j Jura of Pyramid Mount, with Gryphcea dilatata var. Tucum- 



u^ carii, and Ostrea Marshii. Composed of yellow and 



white sandstone, of blue marl, and yellow and white 



limestone. Thickness about 200 feet. 



Keuper or variegated marls of the Trias. 



