KINDERHO OK FORMA TIONS OF MIS SO URI 1 4 5 



means an exact equivalent of the Chouteau limestone of central 

 Missouri, but represents merely the upper portion of that forma- 

 tion. The formation is well exposed along Pierson Creek near 

 the zinc mines, and since it possesses an individuality of its own 

 as a formation, over a rather extensive area, it may be designated 

 as the Pierson limestone. The formation is frequently non-fos- 

 siliferous, but fossils often occur and are usually well preserved. 

 One of the best fossil localities is on the south branch of the 

 Little Sac Creek, about two miles north of Lyman station on the 

 St. Louis and San Francisco railroad. At this locality the fol- 

 lowing fauna was collected which may be taken as a typical 

 representation of the fauna of the whole formation. 



i. Zaphrentis sp. undet. A single imperfect specimen of this genus is 

 the only coral of the fauna. 



2. Leptaena rhomboidalis Wilck. This species is of frequent occur- 

 rence in the fauna. 



3. Oi'thothetes cf. O. inflatus W. & W. A species similar to O. inflatus, 

 but much natter, is rather common in the fauna. The same shell is 

 associated with O. inflatus in oolitic bed No. 6 of the Burlington 

 section. 



4. Chonetes sp. undet. A large species frequently having a width of 

 more than twenty mm is not uncommon in the fauna. It resembles 

 C. illinoisensis Worthern, but is much larger and should perhaps be 

 identified as C, shumardianus DeKon. 



5. Chonetes logani^. & P. ? A species having the general form of 

 C. Log-amis not uncommon in the fauna, but the preservation is not 

 such as to exhibit the characteristic surface markings of that species. 



6. Prodactiis arcuatus Hall. This species is particularly abundant in 

 the oolite bed at Burlington, and the Pierson limestone specimens 

 are of the typical form. 



7. Prodiictus burlingtonensis Hall. Specimens of this species indis- 

 tinguishable from those in Burlington limestone, occur in the Pier- 

 son limestone. 



8. Productus laevicostus White. This species makes its first appear- 

 ance in the Chonopectus sandstone of the Burlington section, and 

 ranges up into the base of the Burlington limestone. 



9. Productus ftunctatus Martin. Specimens of this species are not 

 uncommon in the Pierson limestone. In the Burlington section it 

 makes its first appearance in bed No. 7, the topmost bed of the 

 Kinderhook at that locality. 



