LOWER CRETACEOUS SERIES. 725 



grit, with large inclusions or collections of conglomerate, appearing as if they 

 had been thrown into the soft matrix. 



Many of the pebbles carry Carboniferous coral, crinoids, etc., and from 

 lithologic evidence almost every pebble can be classed with those carrying 

 the fossils. The top of the bed is not seen in Btholen Knobs. 



In Malone Mountain a lenticular horizon of gypsum overlies the conglom- 

 erate. Near the southeast side of the mountain it begins as a narrow strip, 

 and when at the northwest end it develops a thickness of ninety feet. The 

 gypsum is the same in character as that of the two horizons below, and no 

 doubt joins them further into the basin. 



Of necessity these conglomeratic breccias are local, and doubtless did not 

 extend far to the southwest, or into the gypsum forming basin. 



Besides the localities named above for the occurrence of the Etholen beds, 

 they are found forming the low hill immediately north of Etholen Knobs, the 

 clump of hills one and one fourth miles due south of Etholen Station, and the 

 small hill three-eighths of a mile east of Etholen. A clump of the breccia 

 rests upon the flank of Quitman Mountain at the south side of Big Spring 

 Gulch. There is a great development of the conglomerate and breccia in 

 Devil's Ridge, near the northwest side of Eagle Mountain, and they occur in 

 the Devil's Backbone, southeast of Yucca Mesa. 



YUCCA BED. 



In this bed, named because of its development in Yucca Mesa, is included 

 a series of horizons of flaggy marbles, quartzitic sandstones and grit, calca- 

 reous sandstones and arenaceous limestone, and pisolitic limestone conglom- 

 erate in alternating layers, beginning at the great breccia of the Etholen bed 

 and culminating in a second horizon of Caprotina limestone fifteen feet thick. 



The connection between the Yucca Mesa bed and the underlying Etholen 

 breccia is made in Malone Mountain, where there is a large development of 

 arenaceous limestone between the Yucca marble flags and pisolitic limestone 

 and the great breccia. A section of Yucca Mesa will clearly show the con- 

 nection when compared with the middle section of Malone Mountain, which 

 was given on page 722. 



YUCCA MESA SECTION. 



1. Dimly false laminated arenaceous flaggy sandstone, containing small shell 



fragments 48 feet. 



2. Calcareous fucoidal sandstone 8 feet. 



?>. Arenaceous limestone 2 feet. 



4. Limestone, with large oyster in mass 2 feet. 



5. Massive calcareous shell brecciate limestone 36 feet, 



54— geol. 



