6 
SMITHSONIAN INSTITUTION 
The Indiana Area 
Next to Tennessee the most important western Silurian area is in Indiana, 
which is the typical region for the three lower Niagaran formations. The first 
important development there was made by James Hall and under his direction 
at Waldron, in the shale beds which bear its name. Among a wealth of other 
fossils these produced a remarkable crinoidal fauna, containing numerous new 
forms which were described by Hall in several publications from 1869 to 1882. 
Underlying the Waldron, at the town of St. Paul in the same vicinity, is an 
immense exposure of the Laurel formation, a massive limestone of considerable 
thickness, which has yielded a crinoid fauna of a facies markedly different from 
those of the other Silurian members. An excellent collection from this area was 
made by the Doctors Howard, which was accjuired by the Geological Survey of 
Indiana and formed the basis of descriptions by S. A. Miller in the 17th and i8th 
Annual Reports. Dr. C. C. Washburn also made an extensive collection from 
which a choice selection of crinoids passed into my hands, the main collection 
being afterwards acquired by the University of Chicago. Good crinoid material 
was obtained at St. Paul, as well as in the Wabash area to the north and the 
Osgood beds to the south, by A. C. Benedict, and in the Waldron shale at Harts- 
ville by Dr. Moses Elrod, both of which were subsecjuently acquired by me, as 
was also the large collection of Mr. John F. Hammell, of Madison, Indiana, 
which contained important material from all these formations. 
The northern area of Wabash, Grant and Madison counties presents differ- 
ences in the crinoid content from the I.aurel which suggest a connection, in part 
at least, with the Racine dolomite of the Chicago area. The most characteristic 
species of the St. Paul rocks are not found there, although some of the northern 
species are thought to occur at St. Paul. The geology of the Indiana Niagaran 
has been carefully studied by Dr. Foerste, and his papers on the subject will be 
found fully instructive.^ 
Being greatly impressed with the possibilities of the St. Paul exposures of 
the Laurel formation, and the striking character of its fauna as indicated by 
the earlier collections, I made some special efforts from time to time to secure a 
more complete representation of its contents. The crinoids were chiefly con- 
tained in the softer interbedded layers between the beds of massive limestone 
which were extensively Cjuarried for commercial purposes. These layers consti- 
tuted the debris of the quarries left in scattered dumps, in which the specimens 
became exposed by weathering from year to year, affording the main resource 
of the collectors. No prolific colonies were uncovered, and no great quantity of 
specimens was observed, but the preservation was excellent, and new or rare 
forms were always to be expected. Careful overhauling of this material was 
made under my direction during several years by Charles S. Beachler in 1887, 
i2ist Ann. Rep. Dep. Geol. Indiana, 1896, pp. 213-288; 22d ibid., 1897, pp. 195 - 255 - 
