354 C. S. PROSSER 



reported from the Upper Coal Measures of Pennsylvania "an obscure impres- 

 sion which may be that of this species, but very doubtful" (Second Geol. Surv. 

 Pa., Ann. Rep., 1885, p. 455). Mr. Beede writes me, however, that it begins 

 near the base of the Upper Coal Measures of Kansas, and he will shortly 

 publish an article describing the Kansas species of this genus. This species 

 was regarded by Swallow and Geinitz as identical with P. speluncaria Schloth. 

 sp., which is a common Permian form in England and Germany. 



5. Myalina perattenuata M. & H.also occurs near the top of the Marion and 

 is reported from the Permian of Kansas and Texas, and the Upper Coal 

 Measures of Missouri and Illinois. 



The only Brachiopods found are specimens of Derbya from 

 the lower part of the formation, which are doubtfully referred to 

 the species D. multistriata M. & H. sp., which occurs in their 

 Kansas Permo-Carboniferous. The disappearance of the Brachio- 

 pods was perhaps due in part to the diminished depth of the 

 water, but in a much greater degree, undoubtedly, to the highly 

 concentrated nature of the waters, as shown by the deposits of 

 rock salt and gypsum. This change in the condition of the 

 water affected the other forms of life unfavorably ; but there 

 remained, as we have seen, a meager Lamellibranch fauna which 

 differed decidedly from the Lamellibranch fauna of the Coal 

 Measures and is closely allied with the Permian Lamellibranch 

 fauna of Europe. 



The Wellington formation succeeds the Marion, varying in 

 thickness from about 200 feet on the Smoky Hill River to 450 

 feet in Sumner county, near the southern line of the state, 1 in 

 which, as far as known to the writer, no fossils have yet been 

 found. 



The Paleozoic of Kansas closes with the Cimarron group or 

 the Red-beds, which in the southern part of the state are from 

 1 1 50 to 1400 feet thick. 2 The absence of fossils has formerly 

 made the correlation of this group rather indefinite. Professor 

 Cragin has compared the stratigraphy of the Red-beds of the 

 Kansas-Oklahoma basin with those of northern Texas and stated 



1 Univ. Geol. Surv. Kans., Vol. II, p. 67. 

 2 Ibid., p. 88. 



