Fig. 1. — Vertical section through the Ordovician rocks, 

 on the scale of 1200 feet to the inch. 



^ r 



o o 



Jo 



Narrow Vein. 

 Red Vein... 



r 



"O 



Nod Glas. 



§ L^ i 



•»©»••»• 



V V V V V V 

 V V V V V 



■ G-lyptograptus persculptus, etc. 



■ Dieellograptus anceps, Ort/io- 

 graptus truncatus var. n/>- 



■ Trinncleus, Cyclopyge, Christi- 

 ania, etc. 



.Dicranograptus clingani, Dieello- 

 graptus morrisi, D. fureham- 

 ineri, etc. 



...CUmacograptus scharenbergi (?). 



Glyptograptus teretiusculas (?). 



