Stratigraphy of the Missouri Palaeozoic. — Broadhead. 85 
The limestones at the mines are also often much broken and 
sometimes changed to dolomite. Very fine crystals of calcite 
occur at the mines. The Keokuk may be distinguished from 
the Burlington by a few characteristic fossils, as Hemipronites 
crenistria (0. keokuk), Spirifer keokuk and sometimes Ar- 
chimides. The latter fossil is rarely found in southwest Mis- 
souri. Other fossils found in the Keokuk of Jasper county 
are Orthis dubia, Prod net us corn. Pr<><l. alternatus, P. altonen- 
sis, P. jlc in i 'ngi '/'. J', setigerus, P. magnus, J', mesialis, J'. 
wortheni, Sp. pseudolineatus, Sp. subcuspidatus, Sp. lateralis, 
Sp. incrassatus, Sp. logani, Sp. increbescens, Sp. tennicostatus, 
Bhynchonella mutata, Ph. subcuneata, Athyris roysii, Tere- 
bratula parva, Ter.tr inuclea, < 'amoraphoria subtrigona, Zo/i/h,,- 
tis centralis, Amplexus, Phillipsia. 
The lower 20 feet of limestone at Boonville may be con- 
sidered to be Keokuk, the shaly beds above with thin layers 
of limestone and abounding in fossils, including Archimedes, 
Pentremites and crinoidea may he of the Warsaw age. Sim- 
ilar beds are found on Salt river, Monroe county, northwest 
of Paris. At Moscow Mills, Lincoln county, are similar beds 
abounding in Archimedes and corals. 
Genevieve Series. This name has been applied by Prof. H. 
S. Williams to the group of Lower Carboniferous rocks above 
the Keokuk, and includes the St. Louis and ('luster or Kas- 
kaskia groups. On the hills of Jasper and Newton, and at 
other places in northeast and southwest Missouri we often 
find quantities of loose chert, some of it seeming of Keokuk 
age. while other pieces indicate a more recent age. This 
chert contains many fossils, some of them in an excellent 
state of preservation. The chief fossils are Amplexus, Pen- 
tremites conoideus, Actinocrinus, Batocrinus, Spirifer pseudo- 
lineatus, Spirifer increbescens, Athyris plano-sulcata, Rhyncho- 
nella subcuneata, Terebratula fusiformis, Productus cora, 
A thyris ambigua. 
The St. /.(/"is group is better developed in St. Louis and 
St. Charles counties. It is generally thinly bedded, of pure 
limestone, close grained, drab or dove color, durable and af- 
fording a good foundation stone. Make- good lime, and sonic 
beds afford a cement stone. Other beds have been used for 
lithographic purposes. 
