STRAIIGKAPHIC SECTIONS IN UTAH AND ARIZONA. 



67 



Aviculipecten, 3 sp. 

 Acanthopecten coloradoeusis. 

 Acauthopecten? sp. 

 Orthoceras sp. 



Regarding these Kaibab fossils Mr. Girty says : 



The fauna of the Kaibab limestone, which I rogard as 

 of Permian age, presents two fairly distinct fades corre- 

 sponding to different stratigraphic horizons. The upper 

 fauna consists largely of gastropods {especiaXly Belkrophon) 

 and pelecypods (especially Ledn). This is clearly the 

 horizon that was called the " Bellerophon limestone" by 

 the geologists working along the Grand and Green rivers 

 and was regarded by them as the top of the Carboniferous. 

 (See list 1, above.) 



What may be regarded as the normal Kaibab fauna, 

 characterized by such species as Productits ivesi, P. ocei- 

 dentalis, Pustida suhhorrida, and Meehella pyramidalis, is 

 represented (in list 4 above). Those lots containing 

 Squamularia guadalupensis in abundance accompanied by 

 Chonetes killanus form an apprecialile subgi-oup in this 

 fauna and perhaps represent a separate horizon. Essen- 

 tially the same fauna occurs in the San Andres limestone 

 of the Manzano group of New Mexico. (See list 2, above.) 



The coral fauna (list 3, alwve) is unique. It is totally 

 unlike any other fauna in the collection, and I do not 

 recall ever having seen it before. 



The Moenkopi formation was attributed by 

 some earlier geologists to the Permian and by 

 some to the Triassic. Later, largely on the 

 basis of Walcott's work near Kanab, Utah, it 

 was imiversally accepted as Permian, and this 

 assignment received some confirmation from 

 a few very poorly preserved plants that bear 

 considerable resemblance to certain species of 

 the well-kno\ra Permian genus Walchia.^ 

 The Moenkopi formation has been regarded 

 generally as ec^uivalent to the "Permo-Car- 

 boniferous" of the Wasatch Moimtains. The 

 latter beds have lately been proved equivalent 

 to beds in Idaho ■'* whose age is accepted uni- 

 versally as Lower Triassic. The Moenkopi 

 formation must therefore be considered of 

 Lower Triassic age. Mr. Girty's restudy of 

 Walcott's original ''Permian" fossils from the 

 Moenkopi near Kanab, Utah, and the collec- 

 tions made during the present work lend strong 

 support to this correlation. The fossils col- 

 lected by us came from the Rock Canyon con- 

 glomeratic member, at the base of the entire 

 Moenkopi red-bed series, and from the Virgin 

 limestone member. The following combined 

 hsts show the species identified by Mr. Girty: 



'3 Gregory, H. E., Geology of the Navajo country: U. S. Geol. Suney 

 Prof. Paper 93, p. 31, 1917. 



" Girty, G. H., in Butler, B. S., and others, The ore deposits ot Utah: 

 tr. S. Geol. Survey Prof. Paper 111, p. 642, 1920. 



5. Single lot (catalog No. 7791) associated with oil- 

 bearing layer at the oU seep lA miles west of Virgin City, 

 near top of Rock Canyon conglomeratic member; 



BakewelUa sp. (small form). 

 Myalinasp. (small form). 

 Myophoria? sp. 

 Pleurophorus sp. 

 Pseudomelania? sp. 

 Ostracoda. 



6. Single lot (catalog No. 7781) from a horizon 8 feet 

 above that just listed but at same locality; 



Bakewellia n. sp. 

 Pseudomonotis n. sp. 

 Pleurophorus sp. 

 Naticopsis sp. 

 Pseudomelania? sp. 



7. Seven lots (catalog Nos. 7770 to 7775, 7780) from dark 

 fetid limestones in thin sheets in g\-psum beds; all from 

 Rock Canyon conglomeratic member: 



Bakewellia n. sp. (small form). 



Myophoria sp. 



Goniatite or ammonite undetermined. 



Sponge spicules (amphioxes with a few triaenes). 



8. Single lot (catalog No. 7788) from basal conglomerate 

 bed in Rock Canyon conglomeratic member: 



Monotis? sp. 

 Myalina n. sp. 

 Macrocheilina? sp. 



9. Single lot (catalog No. 7794) from horizon 50 feet 

 above base of Rock Canyon conglomeratic member: 



Spirorbis sj). 

 Discina sp. 

 Terebratula sp. 

 Pseudomonotis n. sp. 

 Pleurophorus? (Modiola?) n. sp. 

 Pseudomelania n. sp. 



10. Single lot (catalog No. 7790) from a horizon near top 

 of Rock Canyon conglomeratic member; 



Pseudomonotis sp. 

 Myalina sp. 

 Entolium? sp. 

 Naticopsis n. sp. 

 Bulimorpha n. sp. 

 Pseudomelania?, several n. sp. 

 Turritella, several n. sp. 

 Meekoceras aff . M. mushbachanum. 

 Niunerous undetermined gastropods. 



11. Nine lots (catalog Nos. 7782 to 7787, 7790 to 7792) 

 from the Virgin limestone member: 



Isocrinus sp. 

 Spirorbis sp 

 Pugnax n. sp. 

 Terebratula? n. sp 

 Pinna? sp. 

 Bakewellia n. sp. 

 Pseudomonotis n. sp. 

 Monotis? sp 

 Myalina n. sp. 

 Aviculipecten, 4 sp. 

 Myophoria? sp. 



