USA > Iowa > Hardin County > History of Hardin county, Iowa, together with sketches of its towns, villages and townships, educational, civil, military and political history; portraits of prominent persons, and biographies of representative citizens > Part 9
Note: The text from this book was generated using artificial intelligence so there may be some errors. The full pages can be found on Archive.org (link on the Part 1 page).
Part 1 | Part 2 | Part 3 | Part 4 | Part 5 | Part 6 | Part 7 | Part 8 | Part 9 | Part 10 | Part 11 | Part 12 | Part 13 | Part 14 | Part 15 | Part 16 | Part 17 | Part 18 | Part 19 | Part 20 | Part 21 | Part 22 | Part 23 | Part 24 | Part 25 | Part 26 | Part 27 | Part 28 | Part 29 | Part 30 | Part 31 | Part 32 | Part 33 | Part 34 | Part 35 | Part 36 | Part 37 | Part 38 | Part 39 | Part 40 | Part 41 | Part 42 | Part 43 | Part 44 | Part 45 | Part 46 | Part 47 | Part 48 | Part 49 | Part 50 | Part 51 | Part 52 | Part 53 | Part 54 | Part 55 | Part 56 | Part 57 | Part 58 | Part 59 | Part 60 | Part 61 | Part 62 | Part 63 | Part 64 | Part 65 | Part 66 | Part 67 | Part 68 | Part 69 | Part 70 | Part 71 | Part 72 | Part 73 | Part 74 | Part 75 | Part 76 | Part 77 | Part 78 | Part 79 | Part 80 | Part 81 | Part 82 | Part 83 | Part 84 | Part 85 | Part 86 | Part 87 | Part 88 | Part 89 | Part 90 | Part 91 | Part 92 | Part 93 | Part 94 | Part 95 | Part 96 | Part 97 | Part 98 | Part 99 | Part 100 | Part 101 | Part 102 | Part 103 | Part 104 | Part 105 | Part 106 | Part 107 | Part 108 | Part 109 | Part 110
16, 456
16,636
Audubon
454
1,212
7,448
Benton
672
8,496
22, 454
24,888
Black Hawk
135
8,244
21, 706
23,913
Boone
735
4,232
14, 584
20,838
Bremer
4 915
12, 528
14,0-1
Buchanan
517
7,906
17,034
18,547
Buena Vista.
57
1,5c5
7,537
Butler
3,724
9,951
14,293
Calhoun
147
1,602
5,595
Carroll
281
2, 451
12 351
Cass
1,612
5 464
16,943
Cedar.
1,253
3,941
12,949
19, 731
18,937
Cerro Gordo
940
4, 722
11, 461
Cherokee.
58
1,967
8, 240
Chickasaw
4,336
10, 180
14,534
Clarke
5, 427
8, 735
11, 512
Clay
52
1,523
4,248
Clayton
1,101
3,873
20,728
27,771
28,829
Clinton
2, 822
18,938
35,357
36,764
Crawford
383
2,530
12, 413
Dallas
5,244
12, 019
18,746
Davis
7,264
13, 764
15, 565
16, 468
Decatur
965
8,677
12, 018
15,336
Delaware
168
1,759
11, 024
17, 432
17, 952
19,611
27,256
33,099
Dubuque
3,059
31, 164
38,969
42, 997
Emmett
£25
12, 073
16,973
22, 258
Floyd
3,744
10, 768
14,677
Franklin
1,309
4,738
10,248
Fremont
5,074
11, 174
17, 653
Greene
1,374
4, 627
12, 725
Grundy.
793
6,399
12,639
3,058
7,061
14,863
Guthrie
5,577
12, 988
180
1,389
1,901
Dickinson
10,841
105
1,392
1,550
Fayette
709
821
834
Des Moines
1,244
HISTORY OF IOWA.
68
HISTORY OF IOWA.
.
CENSUS OF IOWA-Continued.
COUNTIES.
1840.
1850.
1860.
1870.
1880.
Hamilton
1,699
6, 055
11,252
Hancock
179
999
3, 453
Hardin
5,440
13, 684
17,808
Harrison
3,621
8,931
16,649
Henry.
3, 772
8,707
18,701
21,463
20,826
Howard
3,168
6, 282
10,837
Humboldt
332
2, 596
6,341
Ida
226
4,382
Iowa
822
8,029
16, 664
19, 221
Jackson
1,411
7,210
18, 493
22, 619
23,771
Jasper
1,280
9, 883
22,116
25, 962
Jefferson
2,773
9,904
15,038
17,839
17,478
Johnson
1, 491
4, 472
17,573
24,898
25, 429
Jones
471
3,007
13,306
19,731
21,052
Keokuk
4, 822
13,271
19, 434
21, 259
Kossuth
416
3,351
6,179
Lee.
6,093
18,861
29, 232
37,210
34, 859
Linn
1,373
5, 444
18, 947
28,852
37,235
Lonisa
1,927
4,939
10,370
12, 877
13, 146
Lucas
471
5,766
10,388
14,530
Lyon
221
1,968
Madison
1,179
7,339
13,884
17, 225
Mabaska
5,9=9
14,816
25,508
25,201
Marion
5,482
16,813
24,436
25, 111
Marshall
338
6,015
17,576
23, 752
Miils
4,481
8,718
14, 135
Mitchell
3, 409
9,582
14,361
Monona
832
3, 654
9,055
Monroe.
2,884
8,612
12,724
13, 719
Montgomery
1,942
16, 444
21,683
23,168
O'Brien
8
715
4, 155
Osceola.
551
4, 419
9,975
19,667
Palo Alto.
132
1,336
4,131
Plymouth
148
2,199
8,567
Pocahontas
103
1,446
3,713
Polk.
4, 513
11, 625
27,857
42,395
Pottawattamie
7,828
4.968
16,893
39, 846
Ringgold
2,923
5, 691
12, 085
Sac
246
1,411
8, 774
Scott
2,140
25,959
38,509
41,270
Shelby
818
2, 549
12, 696
Sioux
10
570
5, 426
Story
4,051
11,651
16,966
Tama
5, 285
· 16, 131
21, 5~5
Taylor.
204
3,590
6,989
15, 635
Union
2 012
5,986
14,980
Van Buren
6,146
17,081
17,672
17,042
Wapello.
8,471
14, 518
22, 346
25, 282
Warren
961
10,281
17,980
19,578
Washington
4,957
14,235
18,952
20,375
Wayne
340
6,409
11, 287
16,127
Webster ..
2,504
10,484
15,950
Winnebago.
168
1, 526
4,917
Winneshiek
546
13,942
23,570
23,937
Woodbury
1,119
6,172
14,997
Worth
756
2,892
7,953
Wright.
653
2, 392
5,062
Total.
43, 112
192, 214
674,913
1, 191, 792
1,624,463
Poweshiek
615
5,668
15, 581
18,936
1,256
5,934
15, 895
Muscatine
5,731
2, 219
Page
5,986
8
12, 270
1, 594
43
.
.
HISTORY OF IOWA.
69
CHAPTER VII
GEOLOGY-TOPOGRAPHY-WATER COURSES.
Geologists divide the soil of Iowa into three general divisions-drift, bluff and alluvial. The drift occupies a much larger part of the surface of the State than both the others. The bluff has the next greatest area of surface, and the alluvial least. All soil is disintegrated rock. The drift de- posit of Iowa was derived, to a consider- able extent, from the rocks of Minnesota; but the greater part of Iowa drift was de- rived from its own rocks, much of which has been transported but a short distance. In northern and northwestern Iowa the drift contains more sand and gravel than elsewhere. In southern Iowa the soil is frequently stiff and clayey. The bluff soil is found only in the western part of the
State, and adjacent to the Missouri river. Although it contains less than one per cent. of clay in its composition, it is in no re- spect inferior to the best drift soil. The alluvial soil is that of the flood plains of the river valleys, or bottom lands. That which is periodically flooded by the rivers is of little value for agricultural purposes; but a large part of it is entirely above the reach of the highest flood, and is very pro- ductive.
The stratified rocks of Iowa range. from the Azoic to the Mesozoic, inclusive; but the greater portion of the surface of the State is occupied by those of the Palæozoic age. The table below will show each of these formations in their order:
SYSTEMS. AGES.
GROUPS. PERIODS.
FORMATIONS. EPOCHS.
THICKNESS IN FEET.
Cretaceous 1
Post Tertiary
Drift.
10 to 200
( Inoceramons Bed.
50
( Lower Cretaceous.
₹ Woodbury Sandstone and Shales
130
( Nishnabotany Sandstone
100
( Upper Coal Measures
200
Coal Measures
Middle Coal Measures
20
( Lower Coal Measures
200
Carboniferous
(St Lonis Limestone.
75
| Subcarboniferous
Keokuk Limestone.
90
1
Burlington Limestone
196
1
[ Kinderhook Beds.
175
Devonian
Hamilton
Hamilton Limestone and Shales
2( 0
Upper Silurian.
Niagara
Niagara Limestone
350
Cincinnati.
Maquoketa Shales.
80
Trenton
§ Galena Limestone
250
Lower Silurian.
(St Peter's Sandstone
80
Primordial
Lower Magnesian Limestone.
250
( Potsdam Sandstone
300
Azoic
Sioux Quartzite
50
Huronian
Trenton Limestone
200
..
-
70
HISTORY OF IOWA.
AZOIC SYSTEM.
The Sioux quartzite is found exposed in natural ledges only upon a few acres in the extreme northwest corner of the State, upon the banks of the Big Sioux river, for which reason the specific name of Sioux quartzite has been given them. It is an intensely hard rock, breaks in splintery fracture, and of a color varying, in different localities, from a light to deep red. The process of metamorphism has been so complete throughout the whole formation, that the rock is almost every- where of uniform texture. The dip is four or five degrees to the northward, and the trend of the outcrop is eastward and westward.
LOWER SILURIAN SYSTEM.
Primordial Group .- The Potsdam sand- stone formation is exposed only in a small portion of the northeastern part of the State. It is only to be seen in the bases of the bluffs and steep valley sides which border the river there. It is nearly value- less for economic purposes. No fossils have been discovered in this formation in Iowa.
Lower Magnesian Limestone. - This formation has but little greater geographi- cal extent in Iowa than the Potsdam sand- stone. It lacks a uniformity of texture and stratification, owing to which it is not generally valuable for building purposes. The only fossils found in this formation in the State are a few traces of crinoids, near McGregor.
The St. Peters sandstone formation is remarkably uniform in thickness through-
out its known geographical extent, and it occupies a large portion of the northern half of Allamakee county, immediately beneath the drift.
Trenton Group .- With the exception of the Trenton limestone, all the limestones of both Upper and Lower Silurian age in Iowa are magnesian limestone - nearly pure dolomites. This formation occupies large portions of Winneshiek and Allama- kee counties and a small part of Clayton The greater part of it is useless for eco- nomic purposes; but there are some com- pact, even layers that furnish fine material for window-caps and sills. Fossils are so abundant in this formation that in some places the rock is made up of a mass of shells, corals and fragments of trilobites, cemented by calcareous material into a solid rock. Some of these fossils are new to science and peculiar to Iowa.
The Galena limestone is the upper form- ation of the Trenton Group. It is 150 miles long, and seldom exceeds 12 miles in width. It exhibits its greatest develop- ment in Dubuque county. It is nearly a pure dolomite, with a slight admixture of silicous matter; good blocks for dressing are sometimes found near the top of the bed, although it is usually unfit for such a purpose. This formation is the source of the lead ore of the Dubuque lead mines. The lead region proper is confined to an area of about 15 miles square in the vicinity of Dubuque. The ore occurs in vertical fissures, which traverse the rock at regular intervals from east to west; some is found in those which have a north and south direc- tion. This ore is mostly that known as Galena, or sulphuret of lead, very small
71
HISTORY OF IOWA.
quantities only of the carbonate being found with it.
Cincinnati Group -The surface occu- pied by the Maquoketa shales is more than 100 miles in length, but is singularly long and narrow, seldom reaching a mile or two in width. The most northern exposure yet recognized is in the western part of Winneshiek county, while the most south- erly is in Jackson county, in the bluffs of the Mississippi. The formation is largely composed of bluish and brownish shales, sometimes slightly arenaceous, sometimes calcareous, which weather into a tenacious clay upon the surface, and the soil derived from it is usually stiff and clayey. Several species of fossils which characterize the Cincinnati Group are found in the Maquo- keta shales, but they contain a larger num- ber than have been found anywhere else in these shales in Iowa, and their distinct faunal characteristics seem to warrant the separation of the Maquoketa shales as a distinct formation from others in the group.
UPPER SILURIAN SYSTEM.
Niagara Group .- The area occupied by the Niagara limestone is 40 and 50 miles in width, and nearly 160 miles long, from north to south. This formation is entirely a magnesian limestone, with a considerable portion of silicious matter, in some places, in the form of chert or coarse flint. A large part of it probably affords the best and greatest amount of quarry rock in the State. The quarries at Anamosa, LeClaire and Farley are all opened in this forma- tion.
DEVONIAN SYSTEM.
Hamilton Group .- The area of surface occupied by the Hamilton limestone and
shales is as great as those by all the form- ations of both Upper and Lower Silurian age in the State. Its length is nearly 200 miles, and width from 40 to 50. A large part of the material of this is quite worth- less, yet other portions are valuable for economic purposes; and, having a large geographical extent in the State, is a very important formation. Its value for the production of hydraulic lime has been demonstrated at Waverly, Bremer county; the heavier piers and other material re- quiring strength and durability. All the Devonian strata of Iowa evidently belong to a single epoch. The most conspicuous and characteristic fossils of this formation are brachiopodes, corals and mullusks. The coral Acervularia Davidsoni occurs near Iowa City, and is known as "Iowa City marble" and "Bird's Eye marble."
CARBONIFEROUS SYSTEM.
Of the three groups of formations that constitute the carboniferous, viz: the sub- carboniferous, coal measures and Permian, only the first two are found in Iowa.
Subcarboniferous Group .- This group occupies a very large area of surface. Its eastern border passes from the northeast- ern part of Winnebago county, with con- siderable directness in a southeasterly direction to the northern part of Washing- ton county. It then makes a broad and direct bend nearly eastward, striking the Mississippi at Muscatine. The southern and western boundaries are to a consider- able extent the same as that which separates it from the real field. From the southern part of Pocahontas county it passes south- east to Fort Dodge, thence to Webster Cits, thence to a point 3 or 4 miles north-
Y
72
HISTORY OF IOWA.
east of Eldora, in Hardin county, thence southward to the middle of the north line of Jasper county, thence southeastward to Sigourney, in Keokuk county, thence to the northeastern corner of Jefferson county, thence sweeping a few miles eastward to the southeast corner of Van Buren county. Its arc is about 250 miles long, and from 20 to 50 miles wide.
The Kinderhook Beds .-- The most south- erly exposure of these beds is in Des- Moines county, near the mouth of Skunk river. The most northerly now known is in the eastern part of Pocahontas county, more than 200 miles distant. The princi- pal exposures of this formation are along the bluffs which border the Mississippi and Skunk rivers, where they form the eastern and northern boundary of DesMoines county; along English river, in Washing- ton county; along the Iowa river in Tama, Marshall, Hanlin and Franklin counties, and along the Des Moines river in Hum- boldt county. This formation has consid- erable economic value, particularly in the northern portion of the region it occupies. In Pocahontas and Humboldt counties it is invaluable, as no other stone except a few boulders are found here. At Iowa Falls the lower division is very good for building purposes. In Marshall county all the limestone to be obtained comes from this formation, and the quarries near Le Grand are very valuable. At this point some of the layers are finely veined with peroxide of iron, and are wrought into both useful and ornamental objects. In Tama county the oolitic member is well exposed, where it is manufactured into lime. Upon exposure to atmosphere and frost it crum-
bles to pieces; consequently it is not valu- able for building purposes.
The remains of fishes are the only fossils yet discovered in this formation that can be referred to the sub-kingdom Vertebrata; and so far as yet recognized, they all be- long to the order Selachians. Of Articu- ticulates, only two species have been recog- nized, both of which belong to the genus Phillipsia. The sub-kingdom Mollusca is also largely represented. The Radiata are represented by a few crinoids, usually found in a very imperfect condition. The sub-kingdom is also represented by corals. The prominent feature in the life of this epoch was molluscan. It overshadowed all other branches of the animal kingdom. The prevailing classes are: Lamellibranch- iates, in the more arenaceous portions; and Brachropods in the more calcareous por- tions. No remains of vegetation have been detected in any of the strata of this formation.
The Burlington limestone formation consists of two distinct calcareous divi- sions, separated by a series of siliceous beds; both divisions are crinoidal. The Burlington limestone is carried down by the southerly dip of the Iowa rocks, so that it is seen for the last time in the State in the valley of Skunk river, near the south- ern boundary of Des Moines county, which is the most northerly point that it has been found, but it probably exists as far north as Marshall county. Much valuable mate- rial is afforded by this formation for eco- nomic purposes. The upper division furnishes excellent common quarry rock. Geologists are attracted by the great abundance and variety of its fossils,-cri- noids-now known to be more than 300.
73
HISTORY OF IOWA.
The only remains of vertebrates discov- ered in this formation are those of fishes, and consist of teeth and spines. Bones. of bony fislı, on Buffington creek, Louisa county, is an exposure so fully charged with these remains that it might with pro- priety be called bone breccia.
Remains of Articulates are rare in this formation; so far as yet discovered, they are confined to two species of trilobites of the genus Phillipsia. Fossil shells are very common.
The two lowest classes of the sub-king- dom Radiata are represented in the genera Zaphrentis, Amplexus and Syringaposa, while the highest class, Echinoderms, are found in most extraordinary profusion.
The Keokuk limestone formation is to be seen only in four counties-Lee, Van Buren, Henry and DesMoines. In some localities the upper siliceous portion is known as the Geode bed; it is not recog- nizable in the northern portion of the formation, nor in connection with it where it is exposed, about 80 miles below Keo- kuk. The geodes of the Geode bed are more or less masses of silex, usually hol- low and lined with crystals of quartz; the outer crust is rough and unsightly, but the crystals which stud the interior are often very beautiful; they vary in size from the size of a walnut to a foot in diameter.
This formation is of great economic value. Large quantities of its stone have been used in the finest structures in the State, among which are the postoffices at Dubuque and DesMoines. The principal quarries are along the banks of the Missis- sippi, from Keokuk to Nauvoo. The only vertebrate fossils in the formation are fishes, all belonging to the order Selachians,
some of which indicate that their owners reached a length of 25 or 30 feet. Of the Articulates, only two species of the genus Phillipsia have been found in this forma- tion. Of the Mollusks no Cephalopods have yet been recognized in this forma- tion in Iowa. Gasteropods are rare; Brachiopods and Polyzoans are quite abundant. Of Radiates, corals of genera Zaphrentis, Amplexus and Aulopora are found, but crinoids are most abundant. Of the low forms of animal life, the proto- zoans, a small fossil related to the sponges, is found in this formation in small num- bers.
The St. Louis limestone is the uppermost of the sub-carboniferous group in Iowa. It occupies a small superficial area, consisting of long, narrow strips, yet its extent is very great. It is first seen resting on the geode division of the Keokuk limestone, near Keokuk; proceeding northward, it forms a narrow border along the edge of the coal fields in Lee, DesMoines, Henry, Jefferson, Washington, Keokuk and Ma- haska counties; it is then lost sight of until it appears again in the banks of Boone river, where it again passes out of view under the Coal Measures, until it is next seen in the banks of the DesMoines, near Fort Dodge. As it exists in Iowa, it consists of three tolerably distinct sub- divisions-the magnesian, arenaceous and calcareous. The upper division furnishes excellent material for quicklime, and when quarries are well opened, as in the north- western part of VanBuren county, large blocks are obtained. The sandstone, or middle division, is of little economic value. The lower, or magnesian division, furnishes a valuable and durable stone, exposures of
G
74
HISTORY OF IOWA.
which are found on Lick creek, in Van Buren county, and on Long creek, seven miles west of Burlington.
Of the fossils of this formation, the vertebrates are represented only by the remains of fish, belonging to the two orders, Selachians and Ganoids. The Articulates are represented by one species of the trilobite, genus Phillipsia; and two ostracoid genera, Cytlira and Beyricia. The Mollusks distinguished this formation more than any other branch of the animal kingdom. Radiates are exceedingly rare, showing a marked contrast between this formation and the two preceding it.
The Coal Measure Group is properly divided into three formations, viz: the Lower, Middle and Upper Coal Measures; each having a vertical thickness of about two hundred feet.
The Lower Coal Measures exists east- ward and northward of the DesMoines river, and also occupy a large area west- ward and southward of that river; but their southerly dip passes below the Middle Coal Measure at no great distance from the river. This formation possesses greater economic value than any other in the whole State. The clay that underlies almost every bed of coal, furnishes a large amount of material for potters' use. The sandstone of these measures is usually soft and unfit for use; but in some places, as in Red Rock, in Marion county, blocks of large dimensions are obtained, which make good building material, samples of which can be seen in the State Arsenal, at Des Moines.
But few fossils have been found in any of the strata of the Lower Coal Measures, but such animal remains as have been
found are, without exception, of marine origin. All fossil plants found in these measures, probably belong to the class Acrogens. Specimens of Calamites and several species of ferns are found in all the Coal Measures, but the genus Lepidoden- dron seems not to have existed later than the epoch of the Middle Coal Measures. The latter formation occupies a narrow belt of territory in the southern-central portion of the State, embracing a superfi- cial area of about 1,400 square miles. The counties underlaid by this formation are, Guthrie, Dallas, Polk, Madison, Warren, Clarke, Lucas, Monroe, Wayne and Appa- noose.
Few species of fossils occur in these beds. Some of the shales and sandstone have afforded a few imperfectly preserved land plants, three or four species of ferns, belonging to the genera. Some of the carboniferous shales afford beautiful speci- mens of what appears to have been sea- weed. Radiates are represented by corals. The Mollusks are most numerously repre- sented. Trilobites and ostracoids are the only remains known of Articulates. Ver- tebrates are only known by the remains of Selachians, or sharks and ganoids.
The Upper Coal Measures occupy a very large area, comprising thirteen whole counties, in the southwestern part of the State. By its northern and eastern boun- daries it adjoins the area occupied by the Middle Coal Measures. This formation contains a considerable portion of shales and sandstone, but the prominent litho- logical features are its limestones. Al- though it is known by the name of Upper Coal Measures, it contains but a single bed of coal, and that only about 20 inches in
75
HISTORY OF IOWA.
maximum thickness. The limestone ex- · posed in this formation furnishes good building material, as in Madison and Fre- mont counties. The sandstones are quite worthless. No beds of clay, for potters' use, are found in the whole formation. The fossils are more numerous than in either the Middle or Lower Coal Measures. The vertebrates are represented by the fishes of the orders Selachians and Ganoids. The Articulates are represented by the trilobites and ostracoids. Mollusks are represented by the classes Cephalapoda, Gasterapoda, Lamellibranchiata, Brachio- poda and Polyzoa. Radiates are more numerous than in the Middle and Lower Coal Measures. Protozoans are repre- sented in the greatest abundance, some layers of limestone being almost entirely composed of their small fusiform shells.
CRETACEOUS SYSTEM.
The next strata in the geological series are of the Cretaceous age. They are found in the western half of the State, and do not dip, as do all the other formations upon which they rest, to the southward and westward, but have a general dip of their own to the north of westward, which, however, is very slight. Although the actual exposures of cretaceous rocks are few in Iowa, there is reason to believe that nearly all the western half of the State was originally occupied by them; but they have been removed by denudation, which has taken place at two separate periods. The first period was during its elevation from the cretaceous sea, and during the long Tertiary age that passed between the time of that elevation and the commencement of the Glacial epoch. The second period
was during the Glacial epoch, when the ice produced their entire removal over consid- erable areas. All the cretaceous rocks in Iowa are a part of the same deposits farther up the Missouri river, and, in reality, form their eastern boundary .
The Nishnabotany sandstone has the most easterly and southerly extent of the cretaceous deposits of Iowa, reaching the southeastern part of Guthrie county and the southern part of Montgomery county. To the northward, it passes beneath the Woodbury sandstones and shales, the latter passing beneath the Inoceramus, or chalky beds. This sandstone is, with few excep- tions, valueless for economic purposes. The only fossils found in this formation are a few fragments of angios permous leaves. The strata of Woodbury sand- stones and shales rest upon the Nishnabot- any sandstone, and have not been observed outside of Woodbury county; hence their name. Their principal exposure is at Ser- geant's Bluffs, seven miles below Sioux City. This rock has no value, except for purposes of common masonry. Fossil re- mains are rare. Detached scales of a lepi- doginoid species have been detected, but no other vertibrate remains of vegetation, leaves of Salix Meekii and Sassfras creta- ceum have been occasionally found.
The Inoceramus beds rest upon the Woodbury sandstone and shales. They bave not been observed in Iowa except in the bluffs which border the Big Sioux river in Woodbury and Plymouth counties. They are composed almost entirely of cal- careous material, the upper portion of which is extensively used for lime. No building material can be obtained from these beds, and the only value they possess,
76
HISTORY OF IOWA.
except lime, are the marls, which at some time may be useful on the soil of the adja- cent region. The only vertebrate remains found in the cretaceous rocks are the fishes. Those in the Inoceramus beds are two species of squaloid Selachians, or certra- cionts, and three genera of teliosts. Mol- luscan remains are rare.
Need help finding more records? Try our genealogical records directory which has more than 1 million sources to help you more easily locate the available records.