Variations of the Ordovician of Indiana. — Focrstc. 95 
f. The Dclinanclla jngosa zone of the Wayncsznlle bed. 
Quite different conclusions might be drawn from a study 
of the DahnancUa zone, at the base of the Richmond, alone. 
On the north side of Hogan creek on the road from Moores 
Hill to Holman, Dabnanella jngosa is common from the base 
of the ^^'ayncsville bed up to 65 feet above ; it occurs in smal- 
ler numbers as far as the base of the Hchcrtella inscnlpta hori- 
zon, at an elevation of 84 feet. South of Friendship along the 
road crossing the southeastern corner of section 13, Dalinand- 
la jngosa is abundant up to 40 feet, the base of the H. inscnlp- 
ta horizon being at 70 feet. Two miles southeast of Belleview 
along a road crossing Indiankentuck river, Dalntanella jngosa 
is common up to 30 feet, the base of the H. inscnlpta laver be- 
ing at 70 feet. South of ]\Iadison, the vertical range within 
which D. jngosa .is abundant diminishes rapidly. At the 
Pinckney Swan locality on Saluda creek it is abundant only 
within a few feet of the base of the Waynesville bed. This 
rapid diminution in the vertical range of Dalmanella jngosa 
between Moores Hill and Marble Hill at first thought sug- 
gested an equally rapid decrease in the thickness of the 
Waynesville bed southward. However, the data recorded in 
connection with the vertical position and range of HehcrteUa 
inscnlpta and DinortJiis siibquadrata do not bear out this sug- 
gestion. 
g. The Madison, Saluda, or Upper RicJimond bcd/^ 
At Richmond the top of the characteristic Middle Rich- 
mond brachiopod fauna occurs 57 feet below the Clinton. 
Southwest of Laurel, at the Derbyshire falls, the base of the 
Tetradium bed is about 71 feet below. At \'ersailles, the in- 
terval is 60 feet. Two miles southeast of Belleview and six 
miles north of Madison, Colnmnaria alveolata occurs 52 feet 
below the Clinton. At Madison, and at Hanover, the inter- 
val is 54 feet. While the coral bed has not been located along 
Saluda creek or at ]\Iarble Hill, the corresponding interval is 
believed to equal or exceed 50 feet. Farther southward, in 
Kentucky, there is a distinct diminution in the thickness of the 
section referred to the ^Madison. 
'Twentihflrst Annual Report. Indiana (Jeological Survey, p. i:20. Amer- 
ican Geologist, June, 10u3. plates XXI, XXII. 
