594 THE JOURNAL OF GEOLOGY. 



the McCloud, for about thirty miles above the junction of the 

 two rivers. 



The Baird Shales. 



Distribution and fossils. The Baird shales consist of about 

 500 feet of black metamorphic siliceous shales, in places calcare- 

 ous, and occasionally sandy. At the top, too, are beds of dia- 

 base and other eruptives, which, however, do not seem to make 

 up any considerable thickness of the rocks. The Baird shales 

 extend from near the junction of the Pitt and the McCloud 

 rivers northward for about twenty miles along the McCloud, but 

 they were studied by the writer only in the neighborhood of the 

 U. S. Fisheries at Baird. 



The strata have a general dip to the east, but this is very 

 inconstant ; their strike is approximately north and south. What 

 underlies them could not be made out. They are certainly 

 younger than the Kennett limestones, but what the interval 

 between the two formations, and whether they are conformable 

 or not, could not be ascertained. They are probably overlain 

 conformably by the McCloud limestone, but the contact could 

 not be observed, and the diabase which separates the two divisions 

 may mark an unconformity. 



Fossils were first cited from the Baird shales by Dr. C. A. 

 White ; T he described from the U. S. Fisheries : Productus gigan- 

 teus, Martin, which is found in America only at this locality, if P. 

 latissimus, Sowerby, cited by F. B. Meek 2 from Montana, should 

 not prove to be a synonym, as Davidson is inclined to think it. 

 Dr. White also mentions several other species : 



Productus conf. nebrasce7isis, Owen. 



Streptorhynchus conf. crenistria, Phillips. 



Camarophoria sp. 



Spirigera sp. 



Fenestella sp. 



Allorisina sp. 



Euomfthalus sp. 



'U. S. Geol. Survey Terr., Twelfth An. Rep., Part I., p. 132. 



2 Bull. U. S. Geol. Survey Terr., Vol. II., No. 4, p. 354. 



