Geology and Mineralogy. 375 



7. The Fauna of the Morroio Group of Arkansas and 

 Oklahoma ; by Kibtley F. Mathek. Bull. Sci. Lab., Denison 

 Univ., vol. XVIII, 1915, pp. 59-284, 16 pis., 5 text figs.— This paper 

 describes the stratigraphy and fauna of what appears to be the 

 oldest horizon in the Pennsylvanian (lowest Pottsville) of America. 

 The study is based on areas in northwestern Arkansas and north- 

 eastern Oklahoma. The Morrow formation consists essentially of 

 shale from 200 to 420 feet thick, with three widely separated zones 

 of limestones to which the various faunules described are 

 restricted. The entire fauna consists of 158 species, of which 79 

 are new and 22 are not identifiable ; at least 39 are well-known 

 Coal Measures forms. From the Mississippian 12 species are 

 derived, representing, among others, the significant genera Pen- 

 tremites, Archimedes, and Glyptopora. Of new genera there are 

 Stereobrachicrinus and Dictyocladia. c. s. 



8. Mississippi, its Geology, Geography, Soils and Mineral 

 Resources ; by E. N. Lowe. Mississippi State Geol. Surv., Bull. 

 No. 12, 1915, pp. 335, 28 figs., 1 map. — This report is educational 

 in scope and treats of the physiography, historical geology, 

 underground waters, mineral resources, and soils of the state of 

 Mississippi. There is also a geological map of the state, c. s. 



9. The Fauna of the Upper Devonian in Montana. Part 2 : 

 The Stratigraphy and the Brachiopoda ; by W. P. Haynes. 

 Ann. Carnegie Mus., vol. X, 1916, pp. 13-54, pis. 4-8, 1 map. — 

 In this good piece of stratigraphic work the author brings together 

 all that is known of the Upper Devonian in the region about 

 Three Forks, Montana, and to this adds his own observations. 

 The fauna consists of 94 species (9 new), and of these 86 are 

 cleai'ly of Devonian time. Only two forms {Rhipidomella 

 vanuxemi, Productella cf. arctirostrata) pass into higher beds 

 which are still beneath the Madison and even then contain 

 "many lower Mississippian forms." The author regards zones 1 

 and 2 as "transitional," though he leaves them in the Upper 

 Devonian. This conclusion is all the more remarkable since 

 these beds have such characteristic Mississippian species as 

 Syringothyris carteri, Cleiothyridina sublamellosa ? ', Camaro- 

 toechia metallica, Schuchertella crenistria, and S. inflata. The 

 evidence, as the reviewer sees it, is not that this faunule is transi- 

 tional but that it clearly belongs in the Mississippian, as certainly 

 as does the Louisiana limestone. c. s. 



10. Origin of the Zinc and Lead Deposits of the Joplin Region; 

 by C. E. Siebenthal. U. S. G. S., Bull. 606, 1915 ; pp. 275 ; 

 11 pis, 16 figs. — This bulletin gives in a brief form a summary 

 of the author's conclusions concerning the origin of the import- 

 ant ore deposits of the Joplin region. It is based upon a study 

 of the district which has extended over a lai'ge number of years. 

 The detailed evidence upon which these conclusions are based 

 will be presented in a later volume. 



The Joplin district is on the western edge of what is known as 

 the Ozark uplift, the center of which is formed by the St. Francis 



