214 



Ft. In. 

 22 — Limestone, with top of layer composed of immense numbers of 



Zijgni^pira modesta 3 



21 — Rather coarse shale 2 



20 — Lumpy, shaly limestone. Asaphus, Rallnesquina 3 



19 — Coarse to tine-grained barren limestone S 



18 — Lumpy, shaly limestone. Rafines(juina (aa), Trilobites (a), Zygo- 



spira, Streptelasma, Bryozoa 12 



17 — Limestone, with Rafinexquina, Zi/gospira (aa), Bryozoa, Oiihoceras. 5 10 

 16 —Shale, with thin layers of limestone 1 



1.5 — Very compact, fine-grained blue barren limestone 6 



14_Shale 8 



13 — Compact limestone. Calymcne, Zygoapira, etc 5 



12 — Limestone. Gdi/mene {&&), Bryozoa, Raftnesquina, Orthoreras .... 1 3 



11 — Shale, with thin layers of limestone 3 8 



10— Tliin argillaceous limestone with Calyviene and Bryozoa (a) 1 



9 — Massive blue limestone.' A'a/mes'/Mi'na, Trilobites, Bryozoa 7 



8 — Limestone. Rnjjnei<qmna, Zyyospira, Bryozoa 2 9 



7 — Thin argillaceous yellow-spotted limestone. Platyntrophm, Heher- 



tclla. Rnfinesquina, Bryozoa 1 



6 — Limestone. Heberte'la (aa), Rajini-sqnina nasuta, Platysstrophialynx. 1 2 



5 — Bryozoal limestone 4 



4 — Covered, probably ^hale 1 



3 — Limestone with Trilobites, Zi/gospira, etc 2 



2 — Coarse crystalline limestone. Ilfheitdla 6 



1 — Covered to river level 62 



Total section 357 



Number 7 of this section represents the top of the Platystrophfa zone. At 

 Vevay the top of the same zone is 358 feet above river level, and at Lawrenceburg 

 about 390 feet. The Madison section afTords an excellent opportunity to study 

 the upper Rafinesquina zone. It is in tlie upi^er zone that this fossil is so con- 

 stantlv associated with Zygospira viodesUi and a number of species of Lamel- 

 libranchs. In the lower zone it has no such constant associates. 



Section along Cliftv creek (jJ 1.12 B) : 



Fc. In. 

 22 — Limestone. Rnfinciquind, Lamellibrancbiata, (Gastropoda, Crin- 



oids 6 



21 — Limestone and coarse lumpy shale 7 4 



20— Shale and limestone. Top, a heavy layer of limestone with con- 

 spicuous wave-like markings ... 21 4 



19 — Partly covered, but represented by heavy layers of limestone in 



the bank above 18 11 



18 —Limestone and shale 14 4 



17 — Limestone. Rafinesquina (aaa), Hebertella 5 



