GEOLOGY AND PALJIONTOLOGY. 



Colonel W. H. Emory, 



Commissioner for the United States and Mexican Boundary Survey. 



Sir : In accordance with your direction, I herewith transmit to you my report relating to the 

 Geology and Pala3ontology of the Boundary Survey. 



The collections of the original survey were placed in my hands, in 1853, hy Dr. C. C. Parry, 

 of the Boundary Commission. These consisted of a series of rocks, minerals, and fossils, 

 collected along the line of the survey, and along the route travelled through Texas. The 

 fossils consisted chiefly of Cretaceous and Tertiary species ; and some of these had previously 

 heen submitted to Mr. Conrad, who described several species in the Proceedings of the Academy 

 of Natural Sciences, of Philadelphia. There were still in the collection a considerable number 

 of undescribed species ; and although placed in my hands for final arrangement and disposition, 

 I preferred that Mr. Conrad should complete the work he had begun, and accordingly trans- 

 ferred the new species to him for description. In the meantime, I had the drawings made and 

 arranged as far as practicable previous to May, 1854. At this time an examination of some 

 collections that had remained in Washington brought to light other species, and the number of 

 figures and plates were increased by these additions. 



The collections of the Survey of the New Boundary, in 1854 and 1855, have also contributed 

 several new species to those previously described, and these I have likewise submitted to Mr. 

 Conrad,* in order that the descriptions might, as far as practicable, possess a unity of character 

 and design. 



The collections have largely contributed to our knowledge of the extent and character of the 

 Cretaceous formation in the southwest. . This information, taken in connexion with the results 

 which have been obtained in the west and northwest, enable us to determine with a great 

 degree of accuracy the character and relations of the different members of the Cretaceous period, 

 as developed in the United States. 



The collections of Palaeozoic fossils contain specimens from the upper carboniferous or coal 

 measure limestone, which is known to become extensively developed in the west and southwest. 

 A single specimen of Asaphus (Isottlus) indicates the existence of lower silurian strata, and since 

 the specimen is scarcely worn, it cannot have been transported from a distance. It is the 

 first specimen of undoubted lower silurian age that has fallen under my observation in all the 

 collections that have been made in the southwest. I should not, however, omit to remark, that 

 a specimen of coral found in the same locality (though exhibiting no decided marks of trans- 



" Except the few species of Ek^inoderms, which, at the request of Mr. Conrad, I have described in their proper place, one only 

 being a new speaies. 



