Plate 6. — Detail of Trap Ridge east of Greenfield. 



Enlargement of the part of plate 5 which lies to the right of the watch in the 

 photograph. A band of the sand and glass mixture extends across from the upper 

 right corner and separates a large, rounded block above from a double block below, 

 whose parts are joined by a narrow neck near the center, while the part to the 

 right sends down a long, curved lobe into the breccia below. This shows one of 

 the forms which can not have been "bombs" in the ordinarv sense. 



XII— Bull. Geol. Soc. Am.. Vol. 8, 1896 



(83) 



