198 KANSAS UNIVERSITY QUARTERLY. 



" On river bluffs above, the red shales at several places carry lenticular forms 

 of gypsum, often snowy, and in quantity sufficient to utilize. There is a mill at 

 Blue Rapids constantly engaged in grinding it up for plaster. Some of these 

 beds are nine feet thick. A strange feature was observed in some of the lower 

 beds of these rocks. In five feet thickness, observed four beds of rock of nearly 

 uniform thickness, sixteen to twenty-five inches, each one with a layer of blue 

 chert on top." 



He does not state which stratum of the above section the last 

 two sentences of the quotation refer to, but from the reading 

 they refer to No. 5, which is the Strong flint. He notes the 

 fossils collected in this section in the following manner : 



^'' Fusulina cylindrica abounds; also found Afhi/ris subtilita, Productus 

 sp.mireticulatus, Chonetes gniiiulifer, J'Jnniicroti.s hawnii, Hemiju'onites 

 crenistrla.'''' 



Dr. G. p. Grimsley also gives a somewhat generalized section 

 of the rocks as they appear in the bluff at the Great Western 

 plaster mill.* 



This section will be seen to compare in a rough way with 

 Broadhead's section, the difference probably being due to the 

 sections being taken at different localities. The top of Grims- 

 ley 's section corresponds to No. 5 of the Broadhead section. 



This formation extends up the Blue river nearly to Marys- 

 ville, and west to Waterville, and on Wildcat creek west of 

 Manhattan, a little beyond Keats. It extends north into Ne- 

 braska, in the vicinity of Summerfield, and is quite prominent 

 in Pottawatomie county. 



THE CHASE FORMATION. 



The Strong Flint. — The geography of this stratum, which 

 forms the base of the Chase formation, is the same as that of 

 the previous formation. It is quite prominent at Keats, Irving, 

 and Blue Rapids. At many other points it is of less marked 

 importance, though always a well-marked terrace or escarpment. 

 The stratum can perhaps be best studied at Waterville and Gar- 

 rison, where the following sections were taken. The one at 

 Waterville is from the west side of the road, north of the Water- 

 ville bridge over the Little Blue river. stratum. Total. 



ft. in. ft. in. 

 .5. Three layers of flint alternating with limestone, some of the 



layers of flint nearly a foot thick in places 4 — 12 — 



4. Limestone, from 1 foot to 4 — 8 — 



3. Calcareous shale 1 — 4—0 



2. Massive limestone, with layer of flint in the top 3—0 3 — 



1, Yellowish shales and covered slope to river-bed. 



*Univ. Geol. Surv. Kans., V, p. 54. 



