124 Bulletin 4 238 



are added to the figures represent the supposed outline of the 

 aperture of the adult shell. 



" The diameter of the coil of the type specimen, when perfect, 

 was apparentl}^ about 180 millimeters. The greatest transverse 

 diameter about 125 millimeters. Some of the specimens already 

 referred to, which were collected in Alabama by Mr. Johnson, 

 indicate a considerably larger size. 



"In Vol. I of the Transactions of the St. lyouis Academy 

 of Science Dr. Shumard described a form under the name of 

 Nautilus texamcs, but which he did not figure. Judging from 

 his description, it seems to agree with the form here described, 

 except for the material difference that it is marked by numerous 

 flexuous transverse ribs, while the surface of our form is evidently 

 plain. The difference between E. ulrichi and most of the other 

 Cretaceous Nautiloid shells of the United States has now been 

 made generic by Professor Hyatt, and specific comparisons are 

 therefore unnecessary. The collection sent by Mr. Ulrich to the 

 Smithsonian containing the type specimens of this species, also 

 contains representatives of numerous other species, but all of 

 them, like these tj^pes, are imperfect. Among them are Callia- 

 nassa ulrichi White, Tubulostiuvi dickhauti White, Gryphcea 

 pitcheri Morton?, Turritella, Ajic/nira, Axincza, Cuadlcsa, etc. 



' ' The type specimens bear the Museum catalogue number 

 8349; and permission to use them in the preparation of this 

 article has been given by the Director of the Museum." 



The surface of this shell is indeed nearly smooth but the 

 substance of the same is quite thick, say at least one-fourth of 

 an inch in many instances. It will be noticed, moreover that 

 Dr. White regards this as a Cretaceous species. This error was 

 first pointed out by I^. C. Johnson in his studies of the Pine 

 Barren region of Alabama in 1883. He showed that the Kn- 

 climatoceras rock overlies a crystalline limestone holding Turri- 

 tella, Cardita, a Rosellaria and other forms. (See Bull. 43, 

 U. S. Geol. Surv., 1887, 65-66). 



Our figures of this species are from electrotype plates made 

 from the originals used in printing Pis. 7, 8, 9 of* Bulletin No. 4 

 of the U. S. Geological Survey. 



This species ranges from the highest to the lowest Midway 

 Eocene bed. (See p. 13). 



Localities. — Texas: Brazos river, about one mile above the 

 Milam-Falls county line; from ^ to i mile up 

 Salt branch from I^ittle Brazos river. 

 Arkansas: Near Olsen's switch, a few miles S. W. 

 of lyittle Rock (type locality). 



