1 66 CHARLES S. PROSSER 



Prodiictiis costatus Sowb. (rr). 



Prodnctus semireticulatus (Mart.) de Kon. (rr). 



Spiriferina kentuckensis Shum. (rr). 



Derbya crassa (M. & H.) H. & C. (rr). 



ArchcEOcidaris sp. Plate and spines (r). 



A little farther west in the upper Green quarry is an excel- 

 lent exposure that differs somewhat from the one just described 

 The section is as follows, commencing at the top of the red 

 shales, No. ii, of the eastern part of the Green quarry: 



Ft. In. Ft. In. 



6. Soil - - - - - - - - - I = 10 5 



5. Light gray to whitish arenaceous deposit (very friable 



sandstone probably belonging to the Dakota) - -56^ 95 

 4. Dark to yellowish brown sandstone ; base of Dakota 



sandstone. Prominent line of unconforrrily - - 8 = 3 n 



3. Massive light gray limestone - - - - i 3 = 3 3 

 2. Yellowish and greenish shales, - - - - -2 ^2 

 I. Top of the red shales (No. 1 1 of the eastern part of the quarry). 



This part of the quarry shows very clearly the line of uncon- 

 formity due to erosion between the Carboniferoas (Wabaunsee) 

 and Cretaceous (Dakota) S3^stems. In places the dark brown 

 Dakota sandstone rests on the gray limestone, No. 3 ; while not 

 more than three feet away the gray limestone is entirely absent, 

 having been worn away before the deposition of the Cretaceous, 

 and the Dakota sandstone rests on the yellowish shales, No. 2, 

 of the section. When this section was studied the upper rocks 

 for several rods had been recently removed, so that the several 

 strata and the line of unconformity were clearly shown. The 

 line of unconformity is shown in the accompanying picture, 

 where the small hammer shows the Dakota resting on the lime- 

 stone of No. 3, and the pick shows it resting on the shales of 

 No. 2. Many of the large blocks of rock from the wall of the 

 quarry showed clearly the line of contact, the non-calcareous 

 brown Dakota sandstone closely united to the yellowish cal- 

 careous shales in which were fragments of shells. A few rods 

 west of the quarry just described, and across a small run, is 

 another large quarry called the Cooley, which gave the foUow- 

 inar section : 



