2 PKOCEEDINGS OF THE NATIONAX. MUSEUM "^'O^. 82 



dropped below the top of the drill-stem, as the drill-stem was 4 inches in 

 diameter, whereas the hole was 9 inches in diameter, and, furthermore, the 

 drill-stem was leaning against the side wall of the hole. 



However, there is a distinct element of uncertainty as to the actual depth 

 from which the specimen was obtained, but I am certain that it came from 

 beds older than the Wilcox formation. 



Some further data are given in a memorandum from H. D. Miser 

 to Dr. J. B. Reeside : 



* * * Core from the Junior Oil Company Beard No. 1 well in sec. 9, 

 T. 18 N., R. 16 W., Caddo Parish, Louisiana, at a depth of 2.460 feet. Ac- 

 cording to Mr. Spooner, the formation from which the core was taken is the 

 Tokio formation of Austin age. 



Although thus considered as probably coming from Cretaceous 

 strata, the specimen is surely of Paleocene age, and probably not 

 earliest Paleocene, as will be shown below. Speculation as to the 

 possibility that the terrestrial mammal-bearing Paleocene is in part 

 equivalent to the marine late Cretaceous is not furthered by this find. 

 It is not certain that the specimen was in place at the recorded 

 depth, although this seems very probable, and it is apparently not 

 certain that the stratum in question does not belong to a post-Cre- 

 taceous intercalation not present, or not recognized, in surface 

 exposures of adjacent regions. The latter would seem the most 

 probable hypothesis on the data at hand. 



Description of the specimen follows : 



Order AMBLYPODA 



Family PERIPTYCHIDAE 



Subfamily Anisonchinae 



ANISONCHUS FORTUNATUS, new species 



Type specimen. — U.S.N.M. No. 12147. Anterior part of skull, 

 with left canine, broken P ^ of both sides, somewhat imperfect M ^'^ 

 of both sides, and other tooth fragments. 



Type locality. — Junior Oil Company Beard No. 1 well, sec. 9, T. 

 18 N., R. 16 W., Caddo Parish, La. 



Horizon. — From an oil well, probably at a depth of 2,460 feet. 

 Formation uncertain, but evidently (from the specimen itself) of 

 Paleocene and probably of Torrejon age. 



Definition ^. — Size of molars about that of A. sectoriits, premolar 

 series relatively smaller and shorter. Molar proportions also about 



1 This definition is so expressed as to facilitate comparison witii revised diagnoses of 

 other species of tiie genus in tlie still unpublished memoir of the Paleocene mammals of 

 the San Juan Basin by Matthew and Granger. 



