EECAPITULATIOK OF PALEOZOIC FOBMATIONS. 165 



of light shale, and 20 feet of dark-blue Carboniferous limestone. This 20-foot bed 

 contains a fauna which is compared with that found near Mystic Lake in Montana, 

 and is without much doubt a member of the Leadville limestone. It is followed by 

 45 feet of light shale, 1.50 feet of light limestone and quartzite, and 50 feet of yellow, 

 red, and white shale. These may belong either to the Leadville or the Weber 

 limestones so far as any information is at hand. The light-colored limestone which 

 I have included with the Leadville is underlain by SO feet of yellow and gray shale 

 and 175 feet of variegated shale with isolated banks of limestone. Both of these 

 beds probably belong to the Farting formation, though here again satisfactory 

 evidence entirely fails. 



In the South Park region the Leadville limestone, as it occurs at Leadville and 

 its vicinit\', has already been described. Information with regard to the region 

 south depends chieflj' upon the accounts of Stevenson and of Endlich, though Peale 

 also has briefly touched upon it. Stevenson usually refers to this formation as the 

 Carboniferous limestone, and he apparently found it at intervals on the west side of 

 South Park all the way from Mount Lincoln to Hunts Peak. He gives no sections 

 and no detailed description. Endlich publishes two sections which include the 

 Leadville beds, but their exact location can not be determined. They occur in the 

 northern portion of his San Luis district and the southern portion of my South Park 

 region. In the section made at ''station 53" the strata which probably belong to 

 the Leadville consist of a grayish-blue limestone, from which were obtained OrtMs^ 

 Prodnctus, and Orthoceras, followed b^'' shales of a gray and brown color, more 

 sandy above, which are in turn overlain bj^ a series of heavj^ strata of dark-blue 

 limestones. The lower limestone rests upon cjuartzites and variegate^ shales, which 

 I refer to the Parting c]uartzite. The fauna mentioned suggests the Devonian fauna 

 of the Ouray limestone or the Mississippian fauna of the Leadville horizon. The 

 upper limestone is followed by a brown sandstone, which is apparently the Maroon 

 or Arkansas sandstone. In this case the Weber limestone or shale is wanting, unless 

 the upper limestone represents it instead of the Leadville. In the section made at 

 "station 56" the Leadville probably comprises a series of blue limestones irregularly 

 alternating with gra}^ shales containing Orthis and crinoids. Bluish shales follow, 

 and are covered in 'turn by a gray sacchai'oidal limestone. Beneath the lower lime- 

 stone ai'e found the quartzites and shales of the Parting formation, while above 

 the upper one comes in a series of red sandstones, which I take to be the Arkansas 

 sandstone and equivalent to the brown sandstone of the previous section. In the 

 two sections just discussed, as well as in that from Fossil Pidge quoted previously, 

 the beds referred to the Leadville formation consist of two limestones separated by 

 shales, but the corresponding members of each series do not agree especially well 

 with each other in lithologic detail. At Fossil Ridge the upper limestone is over- 



