146 University of Texas Bulletin 



the Del Rio clay is 120 feet or more thick, the zone of abundance of 

 Nodosaria is above the occurrence of Exogyra cartledgei Bose, which lies 

 10-30 feet below the Buda limestone. 1 This level probably corresponds 

 to the Grayson formation of North Texas. Nodosaria is rare at Austin 

 in the middle Del Rio clay. At Cerro de Muleros, which is in the northern 

 facies, it is reported as occurring in subdivision 5 (Duck Creek and Fort 

 Worth), and as abundant in subdivision 6 (Denton, Weno and Pawpaw) ; 

 this is its lowest recorded occurrence. 3 



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Berry, E. W. : The lower Cretaceous floras of the world. Maryland Geol. Surv., Lower 

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The upper Cretaceous floras of the world. Maryland Geol. Surv., Upper 



Cretaceous, pp. 183-313. Baltimore, 1916. 



Bose, Emil: Monografia geologica y paleontologica del Cerro de Muleros, etc. Inst. 

 Geol. Mex., Bol. 25, 1910. 



On a new Exogyra from the Del Rio clay and some Observations on the 



Evolution of Exogyra in the Texas Cretaceous. Univ. Texas Bull. 190?, 1919. 



Cotteau, G.: Echinides, in Paleontologie francaise. 



Cragin, F. W. : A contribution to the Invertebrate Paleontology of the Texas Creta- 

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Descriptions of Invertebrate fossils from the Comanche Series in Texas, 



Kansas, and Indian Territory. Colo. Coll. Stud., 5, 1895, 49. 



Dumble, E. T.: The Geology of East Texas. Univ. Texas Bull. 1869, 1920 

 Grossouvre, A.: Recherches sur la Craie Superieure. I. Stratigraphie generale. 



II. Paleontologie. Paris, 1893-1901. 

 Haug, Emile: Traite de Geologic. Paris, 1911. 

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Ann. Rept., Pt. 7, 1901. 



Geology of the Territory adjacent to the Red River in Arkansas, Texas. 



and Indian Territory. Bull. Geol. Soc. Amer., 5, pp. 297-338, 1893. 



Noetling, F.: Die Fauna der baltischen Cenoman-geschiebe. Pal. Abh., BH. II. heft 4, 



1885. 

 Pervinquiere, L.: Etudes de paleontologie tunisienrie. I. Cephalopodes des terrains 



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Paleontologie, tome xvii, fasc. 2-3, Mem. No. 42, pp. 1-86, pis. 1-7 (x-xvi), 1910. 



'Bose, Univ. Texas Bull. 1902, p. 19, 1919. 

 -Bose, Inst. Geol. Mex., Bol. 25, pp. 24-26, 1910. 



