122 BuivIvETIN 4 236 



Cephalopoda. 



ENCLIMA TOCERAS. 

 Endiniatoceras iclrichi, Pis. 13, 14, 15. 



Syn. Nautihts texanus White, Proc. U. S. Nat. Mus. , vol. iv, 



1881, p. 137. 

 Enclimatocei'as (^Nautilus) ulrichi White, Bull. U.S. Geol. 



Surv. , No. 4, 1884, p. 17, pis. 7, 8, 9. 

 Ejiclimatoceras hyatti A\d., Bull. Geol. Surv. Ala., No. i. 



1886, p. 60. 

 Endiniatoceras ulridii Harris, Ann'l Rep't Geol. Surv. 



Ark., 1892, p. 36. 



This fossil being obviously one of the most characteristic of 

 the Midway stage from Texas to Alabama inclusive, it is deemed 

 advisable to here insert Dr. White's account of it together with 

 his original description as found in Bulletin No. 4 of the U. S. 

 Geological Survey, pages 16 and 17. 



"On the Nautiloid Genus Enci^imatoceras Hyatt, and 

 A Description of the Type Species. 



"In the year 1880 Mr. E. O. Ulrich sent to the Smithsonian 

 Institution a small collection of fossils which he had obtained 

 from the Cretaceous strata near Little Rock, Ark. A part of 

 these fossils were described by me in Vols. Ill and IV of Pro- 

 ceedings of the United States National Museum; but the Nau- 

 tiloid shell now described was then only casually noticed. Its 

 peculiarities were recognized at that time, and the specimens 

 were laid aside with the hope that better material might be 

 procured for study. Other specimens belonging to this or a 

 closely related species were afterward collected by Mr. Lawrence 

 C. Johnson from strata supposed to be of Cretaceous age, in Wil- 

 cox county, Alabama, but they are no more perfectly preserved 

 than the Arkansas specimens. 



' ' Prof. Alpheus Hyatt having had in hand an exhaustive 

 work on Nautilus and its allies, the Arkansas specimens were 

 placed with him for examination. In a preliminary work of his, 

 just published, he divides the genus Naidilus as it has been 

 generally recognized, into numerous genera besides those pre- 

 viously proposed by other authors. To one of these groups he 

 has given the generic name Endiniatoceras, and made the species 

 here described the type of the genus. The following is his 

 generic diagnosis, which he has also published in the Proceed- 

 ings of the Boston Society of Natural History, Vol. XXII, 

 1884, p. 270. 



