BIBL10GR.VP1IY AND NOTES 083 



No. Date. 



.ohscura Stanton; Pinna sp. ; **Actwon propiuquus Stanton. 

 (Those marked * are said to be of Pierre age, and those 

 marked ** to be of Benton age.) 



(P. 58) About IG miles southeast of Cabezon (probably' near 

 the top of the Mancos shale) the following fossils were found: 

 Frionotropis woolyari (Mantell) ; Placenticeras placenta (L)e- 

 kay) ; Astarte evansi (H. & M.) Whitfield, and 7 miles farther 

 southeast, at about the same horizon as those named above, the 

 following were collected : Gryphwa newheiryi Stanton ; fnoccra- 

 mus labiatus (Schlotheim); Inoccramus dimidius var. labia- 

 toides S. and B. ; ? Yoldia suhellipiica Stanton ; Anomia propa- 

 toris White; Ostrea luguhris Conrad; Ostrea anomioides var. 

 nanus Johnson ; Cardiinn paiiperculuni Meek ; TurriteUa ichitei 

 var. stantoni S. and B. ; Lunatia concinna (H. and M. ) ; Friono- 

 tropis hyatti Stanton; Frionotropis woolgari (Mantell). 



(Pp. 59-60) Evidence is given to the effect that there arc two 

 "Septaria zones" below the "Caphalopod zone" of Herrick and 

 Johnson, which contain a fauna said to be "almost totally dis- 

 tinct from the Septaria fauna. The authors conclude that the 

 strata yielding the fossils described vary in age from Benton to 

 doubtful Pierre and "show a commingling of many species of 

 the Colorado formations with a few of the Montana. This 

 would apparently indicate an upper Fort Benton age for the 

 beds unless we suppose that the apparent absence of clear water 

 in this region during Niobrara times would cause the absence of 

 the typical Niobrara fauna and the persistence of the Fort 

 Benton fauna to Montana times. Under such a supposition, 

 some of these intermediate strata would represent the Niobrara 

 time, without the presence of the typical Niobrara fauna." 



110. 1909. Gardner, .James H. : The coal field between Gallina and liaton 



Spring, New Mexico, in the San Juan coal region. 



U. S. Geol. Survey, Bull. 341, pp. 3.35-351, 1 pi. (map). 19U9. 



Two coal-bearing formations southwest of Nacimiento Moun- 

 tains are described. They are the Mesaverde, which includes 

 Schrader's "Upper Montana Group," an(i the "Laramie." These 

 are separated by Lewis shale, which is said to be 2,000 feet thick 

 near Gallina and only 250 feet thick on the Arroyo Torreons, about 

 30 miles to the southwest. Several geologic sections are given 

 showing the relations of the coal beds to other rocks. 



(P. 338) "At a point 10 miles north of Gallina a part of the 

 (Mancos) becomes arenaceous and forms a hogback in the shale 

 valley. This sandy bed is about 30 feet thick and about 275 feet 

 below the top of the formation. It is no doubt the beginning of 

 the sandstone and shale formation that increases in thickness 

 toward the south and is coal-bearing on the south side of the 

 (San Juan) basin." 



111. 1900. Lee, Willis T. : Unconformity in the so-called Laramie of the 



Raton coal field. New Mexico. 

 XLVIII— Bull. Geol. See. Am., Vol. 23, 1911 



