1921] EDWARDS AND RAASCH, UPPER DEVONIAN STRATA. 93 



nodules of marcasite. Tentaculites, Lingula and other brachiopods, and 

 a dwarf faunule of gastropods and goniatites, all completely preserved 

 in marcasite, are frequently found at this horizon. Fish remains occur 

 in abundance, usually consisting of plates and fragments of the bony 

 armor, sjMnes, and dental plates of Ptyctodus and allied forms. Im- 

 mediately adjoining the conodont band are found the remains of plants 

 resembling Calamites in their general appearance. 



Two other closely associated fossiliferous bands occur, apparently, 

 at a higher horizon in this member. Both of these are found in greenish 

 and rather coarse-grained shale forming thin bands in the fissile black 

 shales. One of these, a few inches in thickness, is characterized 

 by various genera and species of pelecypods, the Ledidea and pectneate 

 forms predominating. In addition, brachiopods ( Productella, Cnonetes, 

 Camarotoechia. etc.). gastropods ( Bellerophon, Platyceras, etc.) Spor- 

 angites, and a few conodonts also occur. The other of these fossilifer- 

 ous bands is characterized by conodonts associated with worm trails. 

 They occur in a layer of very hard, and resistant shale which is fre- 

 Cj[uently wave-marked and cross-bedded. This layer is seldom more 

 than an inch in thickness. 



These three shaly members with their included fossiliferous bands 

 appear to belong to a single formation which is here named the Ken- 

 wood formation, after the section of the city of Milwaukee in which 

 the typical exposures occur. This formation may be defined as includ- 

 ing all the strata overlying the Hamilton in these exposures. Its age 

 as determined from its location in the section and its fossil content is 

 lower Upper Devonian. The lithological character of the rocks and the 

 fauna of conodonts, etc., suggest a close correlation with the Genesee 

 shales of New York and the Antrim shales of Michigan. The dwarf 

 pyrite fauna occurring at the base of the Genesee in western New York 

 also seems to be represented in the faunules from the Intake Tunnel by 

 the dwarfed and pyritized gastropods and goniatites present in a single 

 one of the fossiliferous horizons. 



The presence of such a rock and fauna at the top of the Hamilton 

 of this region is to be expected from its wide distribution at the base 

 of the Upper Devonian in New York, Michigan, Ohio, and Indiana. 

 As has been suggested by others, it is very probable that a large portion 

 of the basin of Lake Michigan has been excavated in these soft, shaly 

 rocks. The possible occurrence of this formation in Wisconsin is lim- 

 ited to the shore area of Ozaukee and Milwaukee counties. 



