584 CONGLOMERATE ROCKS. 



This occurs, but in limited quantity, where 

 these two rocks are associated. 



I. Sandstone with quartz. 



a. The quartz in angular fragments. 



b. The quartz in rounded nodules or 



united with angular fragments. 



K. Sandstone and limestone united. 



a. Fragments of sandstone imbedded in 



limestone. 



b. Fragments of limestone imbedded in 



sandstone. 



c. A congeries of fragments of these two 



rocks. 



These are general conglomerates, and belong 

 to the secondary sandstones, but chiefly to the 

 lowest. They are enumerated under the heads 

 of the respective rocks to which they belong, and 

 of which they form constituent portions. 



L. Sandstone and argillaceous schist, or shale, 

 united : general. The fragments of the schist are com- 

 monly imbedded in the sandstone. Belongs like I and 

 K to the different sandstones, where it is also enume- 

 rated. 



THIRD DIVISION. 



Consisting of three or more substances or 

 rocks united. 



