S64 



N. H. DAttTON FISH REMAINS IN ORDOVICIAN ROCKS 



cauda, and I. milleri. Of these 11 species pass up into the fauna 180 

 feet above. 



MANITOU REGION 



At Manitou and for some distance northward and in the Trout Brook 

 valley ( Manitou park) Manitou limestone underlies the Fountain Eed beds. 

 On Trout brook this limetsone has yielded distinctive Ordovician fossils. 



105° 103° 



Figure 6. — Map of a Portion of the Northwest, showing Distribution of Ordovician. 



Throughout this area it is underlain by Cambrian sandstone. Near 

 Manitou there are several hundred feet of limestones, of which the lower 

 portion is Manitou, while the upper members, according to A. W. Grabau,* 



* G. H. Girty : Carboniferous formations and faunas of Colorado. Professional paper, 

 U. S. Geol. Survey, no. 16, 1903, p. 168. 



