|KANSAS COLLECTION BOOKS|
FOSSILS OF THE NIOBRARA.
The Niobrara is the upper formation of the Cretaceous period, which embraces the latest division of Mesozoic time. In the rocks of this period, reptiles first became numerous and predominant, as shown in the fossils, which are so numerous, as compared with others, as to mark the period as the age of reptiles. The fossils, however, are not confined to them, but cover the whole age of co-existent vegetable and animal life.
Fossils of marine plants are occasionally found, but evidences of land vegetation are confined to a few specimens of fossilized wood, which are found but seldom. Such as have been found showed frequent marks of boring by some land insect or animal, showing that the early vegetation of that period had brought with it the same animate elements of destruction against which it now contends. Occasionally, a specimen found is carbonized or charred, and burns readily; while more frequently it appears in all stages of the process of crystallization, from the partially-decayed wood to the fully-completed transformation into chalcedony, with the annual marks of the growth still distinct. Of the species, few have been identified with those of the present time. Prof. Mudge states that, in a single instance, he detached the fibrous structure of the palm. This alone marks the climate of that age as tropical, if it was of indigenous growth. Leaves appear rarely, though common in the Dakota formation below, and in the Tertiary of Colorado above. Islands must have existed in this cretaceous ocean, as the homes and breeding places of the birds whose fossils have been found, as well as the resting places for the amphibious animals which were then numerous. They may have been only the bare surface of the rocks covered with soil so sparsely as to preclude the growth of trees.
The fossils of the cretaceous sea, as found in the Kansas formation, embrace a wider range and give a larger proportion of the whole number known to scientists as cretaceous fossils than any other section of the system in America. Those discovered include many specimens rarely found elsewhere. Specimens of the only Crinoid known to the American cretaceous were found by Prof. Mudge; also rare mollusks, one of which, a large bivalve, measured from thirty to thirty three inches in length. He also notes the discovery, by his party, of a bed of baculites, near Sheridan, a species of shell fish, not found nearer than New Mexico. Many other specimens are named by him, which it is unnecessary to note, having no great interest to any but the scientific reader.
The vertebrates are everywhere found-fishes, saurians, birds-so profuse in number and variety as to render it one of the most interesting fields of exploration for the paleontologist in America. Prof. Mudge has more thoroughly examined the field than any other person, being employed for the seasons of 1874, 1875, 1876, 1877, with from two to five assistants, in collecting vertebrates from this section for Yale College. Of the specimens gathered, he says:
"The least interesting are the fish, which have, however, given us many new species, and some new genera. The small ones are nearly entire, but the larger ones are represented only by well-preserved portions of the skeletons. Teeth of selacians (shark genera) are quite common. At one locality, over 400 were collected in an area of thirty inches, and apparently from the jaws of the same individual - Ptycodus mortine - and all in excellent preservation."
Among the rare specimens discovered, he notes a new genus, which has a long, conical-shaped snout, composed of a compact bundle of fiber, which was appended to the skull like the sword of the sword fish. The snout in the largest specimens was fifteen inches long. During the season of 1875, his note-book recorded the observance of 1,207 specimens of vertebrate fish, not including sharks' teeth, which were too plentiful to be worthy of note. Several species of marine turtle were discovered different from those now living, the type being embryonic. The largest, described by Prof. Cope, in his "Cretaceous Vertebrata," with flippers extended, had an expanse of fifteen feet. Several smaller species were discovered, showing no embryonic features, one being about the size of the fresh water turtle now found in Kansas.
The singular and most interesting feature of the Niobrara fossils, both to the scientific and general reader appears in the types of reptiles so numerously represented. The saurian, or lizard tribe, seem, at that period, to have held full sway in Kansas. Prof. Cope in his list of all the genera and species of the saurian type in America and Europe, known to the Cretaceous period, enumerates fifty-one, of which number Europe furnishes but four, while the small strip of Niobrara in Kansas furnishes thirty-six. In the same formation in Nebraska, few fossils of the vertebrates are found. The explorations made by Prof. Mudge were made mostly in the Saline and Smoky Hill Valleys, where the supply of fossils was abundant. Of his success in collecting saurian specimens, he writes as follows:
"Our labors during four years past have added much to the knowledge previously obtained in regard to the structure of this class of reptiles, particularly of the smaller bones and hind limbs. The collections from Kansas in the possession of Prof. Marsh, will leave little to be needed in the study of the anatomy of saurians, as they are more full and complete than any in Europe."
The number of specimens seen by Prof. Mudge and his party, during the season of 1875, was four hundred and seventy-six, of which number, he says one-half might be called good, and some of them equal, if not superior to anything previously found in Europe or America. The saurians are of all sizes, usually from twenty to forty feet in length; one monster, the fossil remains of which were found in Jewell County, was nearly seventy feet long; two species discovered, did not exceed six feet in length. The monstrous hideousness of these reptiles when clothed with flesh, and clad in scales,* similar to a snake, with eyes the size of an ordinary dinner-plate, with jaws giving an orifice to the mouth of from three to six feet, armed with saw-like teeth, can be safely left to the imagination of the most unscientific reader. The specimens are not evenly distributed, sometimes for miles along the slides and ravines where they are usually discovered, none are visible, while in some small areas the specimens were abundant. From this, Prof. Mudge inferred that the animals frequented favorite haunts, to the exclusion of larger areas.
The petrified excrement of these monsters, known to scientists as coprolites, abounds in the regions they inhabited. The coprolites are in substance a little harder than chalk, and finer grained. They contain frequently the bones of the food, and, in connection with the indigestible portions of food frequently found between the ribs where the stomach was located, show in what it consisted. They fed mostly on small fish; some crustaceans (of the crab species) occasionally appear in the formation. That they were ravenous feeders, with vigorous digestive powers, appears from the large proportion of bones; sometimes amounting to one-fourth the weight of the coprolite in which they are found. In the plesiosaurs, one of the monsters of that period, having a long serpent-like neck, attached to the crocodilian body, between the ribs, in the cavity of the stomach were found well worn silicious pebbles, from one-fourth to one-half inch in diameter; aids to digestion, similar to those in the stomachs of some reptiles and birds now existing. Prof. Mudge, remarking on this fact says, that They were the more curious, as we never found such pebbles in the chalk or shales of the Niobrara. How far the saurians wandered to collect them is a perplexing problem. Their structure does not indicate much ability to crawl on land, and yet it is probable that they frequented some of the islands of the old cretaceous ocean for that and other purposes. As such substances remain in stomachs of low organization for a long time, the visits to dry land would not necessarily have been very frequent. Sharks teeth were frequently found in the remains of the food, showing the savage voracity of the animal that could master and devour the most formidable and ravenous fish known. They did not however, always escape unscathed in their battles with these tigers of the sea. The marks of their jaggy teeth are often found on the bones of their enemies. Frequently the ribs were found fractured and again united while the animal lived. In one instance Prof. Mudge discovered in a saurian specimen a most serious injury in the spine, which the monster had outlived. His relation is as follows: Five of the vertebrae had been fractured so seriously as to destroy many of the spinous processes, after which it had healed, but the whole had grown together (anchylosed) so as to lose the natural form of the separate bones and become a confused firm mass. When we know that the largest (Brimosaurus, Leidy) was seventy feet long, with a head six feet, those of half that size should avoid an encounter; and those only six feet in length might have been swallowed whole.
Still more interesting than the saurian fossils, are those of the pterodactyls, which, except in one or two isolated cases, have been found no where in America except in the Niobrara of Kansas. They were the birds of the period, although, strictly speaking, not birds at all. They were of the genus pterosaurs, signifying reptiles with wings. The pterodactyl, as signified by its name, was wing fingered; the bones of one of the fingers of the forearm being greatly elongated, for the purpose of supporting an expanded membrane, which served, like the analogous arrangement in the bats, for flying. As bats are flying mammals, so pterodactyls were flying reptiles, resembling bats more nearly than birds. Those of Kansas differ widely from the European type, having no teeth like their foreign cousins, and a less elongated and beak-like head. On these divergences in structure, shown in the Kansas specimens, Prof. Marsh has based a new suborder, of two genera, - pterodontia. - of which he describes six species, all furnished from the Niobrara of this State. The American specimens have the claws or hands and the general structure of the body reptilian, with the elongated head of the saurian, destitute, in the true American pterodactyl, of teeth. They have membranous, bat-like wings and the hollow, light, bony structure of birds. They are larger than the European species, several having been discovered with a stretch of wing varying from twenty to twenty-five feet. In one instance Prof. Mudge states that he uncovered the wing finger of a pterodactyl, the bones of which measured five feet eight and three-fourth inches in length. His note-book shows seventy-two individual specimens of this flying reptile, as seen during the season of his explorations in 1875.
Of the fossil birds of the Niobrara beds of Kansas, Prof. Mudge reports as follows: In Dr. Cones Key to North American Birds, published in 1873, Prof. Marsh has given a list of the fossil birds of the cretaceous of North America, at which time thirteen species were known, all first described by himself. Of these, five are from the Niobrara beds of Kansas. To this we have added two species, making (as some others are not yet identified) at least seven from Kansas. Five of these are so anomalous as to be provided with jaws and teeth. These Prof. Marsh described as a sub-class, odontornithes. In the odontolcae, we have birds of the largest class of aquatics, measuring five to six feet in height. The teeth are set in grooves in the jaws. The wings are very rudimentary, too weak for flight. The odontotormae, on the other hand, are small, with strong wings, giving great power of flight, and the teeth are set in sockets. And what is more singular, the vertebrae are biconcave, like a fish, but still retaining the bone structure of the bird.
The Fort Benton formation, lying directly beneath the Niobrara, is found east of the Niobrara section. Prof. Mudge says: It is seen as far south as Walnut Creek and Pawnee Creek, in Ness County, but better developed in the bluffs of Smoky River, southwest of Fort Hays, as well as seven miles west of that place. It can thence be traced to the northwest, crossing the Solomon just above the Forks, near Osborn City, and entering Nebraska in the Republican Valley, near where that river crosses the State line. The upper portion of the Benton group consists of a heavy bed of soft, fine-grained limestone, varying in thickness from thirty to sixty feet. It lies along the east line of the Niobrara, and from its massiveness and persistency, shows a well defined horizon between the two groups. It is laminated, the layers being from one to three feet thick. It is an excellent building stone, and, when burned, yields good quicklime. Below the limestone is a stratum of some sixty feet of soft, slate-colored shale. It abounds in flattened nodules of hard clay marl (septaria) varying in diameter from one inch to six feet. They are frequently threaded with cracks lined with crystals of calc-spar, which sometimes extend to the outer edges of the concretions, being filled with white lime. These latter, with their fancifully defined proportions, are often mistaken for fossil turtles. Below this to the bottom of the Benton group, one hundred and forty feet, are shales varying in color and hardness, and interstratified by layers of limestone, composed largely of marine shells. All the strata below the heavy upper bed of limestone are variable in their composition, the predominant component being on the same horizon, clay, sand or lime as the case may be. There is no thick, persistent stratum of any kind. The total thickness of the Benton group, as given by Prof. Mudge, is two hundred and sixty feet.
As a part of the cretaceous system and directly underlying the Niobrara, where evidences of animal life are so profuse, it might naturally be expected that a like abundance of fossil remains would appear, of saurian type, as well as fish and birds. But few fishes or saurians have been discovered, and no pterodactyls or birds. In the Saline and Solomon Valleys, the fossils of ammonites, in great numbers and variety are found. Several different species appear, varying in diameter from one to thirty inches. The ammonite was a chamber-shelled mollusk, akin to the nautilus. Prof. Dana states that over 1,000 species of the ammonite group occur in the Mesozoic Rocks, the last then, or early in the Tertiary; 500 species of the nautilus tribe have been in existence; now there are but two or three. The only vegetable or wood fossils are the thin and impure beds of lignite (brown coal) which sometimes appear in the lower strata. No plants could be identified from these.
The Dakota group is the lowest in the cretaceous system, resting directly on the Upper Carboniferous (Permian) group.* The prevailing material of this formation is sandstone, brown and variegated in color. It varies in compactness from that which can be easily crushed between the fingers, to the hardest, which requires the heavy blows of the sledge to fracture. The more compact formations owe their hardness to the presence of the oxides and silicates of iron. It furnishes wherever found an excellent building stone. In some places, a poor quality of limonite (brown iron ore) is deposited. The most frequent overlying or inter-stratification is of clay shale of varying color. In the ledges are found concretions of curious and fanciful form, some hollowed out like a bowl or vase; others are in the form of tubes, some as large as three inches in diameter and eight feet in length. Of these concretions, Prof. Mudge says that some are glazed and distorted, as if they had been subject to the action of fire. He attributes this appearance, not to any application of heat, but to the oxidation of iron, giving in support of his conclusion the fact that within the tubes are frequently inclosed well-preserved fossil impressions of leaves which would have been destroyed by the action of fire. The concretions of the white sandstone are sometimes found in disk forms of several feet in thickness, and six to eight feet across. The softer formation of sandstone on the sides and partially underneath, being wasted or washed away. They remain as tablets, supported by one or more columns of the sandstone still remaining, in shape very like a toadstool where the supporting shaft is single. Where the erosion has been only on the sides, and not sufficiently low to sculpture the column beneath, they rest on the surface of the ground, and in their appearance resemble a cluster of old-fashioned, cone-shaped bee-hives, or considering their size, more nearly, a lot of well-built, petrified hay-stacks. Near Minneapolis, Ottawa County, the latter formations are profusely and beautifully represented. In Ellsworth and Lincoln Counties, the pillared specimens are seen showing rare symmetry of proportion, and marked similarity to human handiwork.
The average width of the Dakota is something less than fifty miles, being the widest in the southern part of the State. It varies in thickness, the maximum being, according to Prof. Mudge, 500 feet. It corresponds to the Cretaceous of Swallows report, together with Nos. 2 and 3 of what he doubtfully classes as Triassic, which, under his classification, also covers the upper part of the Permio-carboniferous, as laid down by Prof. Mudge, whose stratigraphical order is followed in the sketch.
The fossil fauna of this group consists only of a few marine mollusks, fish and saurians of little interest, either from their abundance or novelty, except to scientists, who, from the small supply, have found several new species of mollusks, and an interesting and rare variety of fish, similar to the flying fish of the present period.
The flora of this group is varied and interesting, as representing the first and abundant growth of Dycotyledonous trees and plants. The term signifies that the seeds have two cotyledons, or lobes, which in germinating divide into parts. They have the seeds following regular flowers, and are exogenous; the plants having a bark, and rings marking the annual growth. They are sometimes designated by scientific writers, by the scarcely less formidable name of Angiosperms, or seed covered, the seeds being inclosed in an outer covering. Of this species are the maple, elm, apple, rose and most of the trees and shrubs now beautifying the earth, hence, the unscientific reader may contemplate with interest the period that saw the primeval existence of the trees and shrubs which still flourish. They are found mingled with the coniferous and older growth of pines and cedars, and at all depths from within thirty-five feet of the Permian to within forty feet of the overlying Benton strata. The woods are seldom found, but the leaf impressions appear generally in their layers and strata, extending horizontally along ravines or around a hill. The leaves are generally an almost perfect state of structural preservation, the outlines of the veins and veinlets being so distinctly traced in the stone as to be easily recognized, if of any known species. Imperfect specimens of fruit, and a few fragments of wood and bark have been found. The leaves seem to have grown on trees along the shore line of islands, and to have been wafted into the sea, and there imbedded in the marine sediment immediately after dropping. More than half of the dicotyledonous plants catalogued by Prof. Lesquereaux in his Cretaceous flora, have been found in the Dakota of Kansas. Among them are five species of poplar, six of willow, eight of oak, six of button-wood, seven of sassafras, five of magnolia, two of fig, two of cinnamon and one of palm. The three last named indicate a warmer climate than now prevails. The single species of palm was found lower down geologically than the others enumerated. It was discovered by Prof. Mudge in the northwest corner of Marion County, and was classified by him as of the same genus as the palmetto, which now grows in South Carolina. In addition to the Angiosperms, several conifers have been found; among them a pine, and four species of the gigantic red-wood of California, one of which was closely allied to those still existing.
This sudden influx of modern vegetation, in full type, during that period, renders its fossil flora more interesting than that of any other shown in the geological structure of Kansas.
UPPER CARBONIFEROUS AREA (PERMIAN*.)
Prof. Swallow determines them Upper and Lower Permian, placing them
immediately beneath the Dakota of Mudge, which he classes as probably
Triassic, and over the carboniferous system. His belief that they represent
and are identified with the Permian is based on the fact, as stated in his
preliminary report on State geology in 1866, that the fossil mollusks of these
strata, so far as observed, belong mainly to the Acephela (headless)
and Cephelapoda (with feet or tentacles attached to the head), and the
Gasterpoda (belly-footed or crawling on the ventral surface), which, he
affirms, have not been identified with known carboniferous species. He notes
the fact that the Lower Permian rocks contain nearly or quite all the fossils
found in the Upper Permian, and, in addition, a few species common to the
Upper Coal Measures, and perhaps a few species not found above or below. He
also notes the fact that the general character of the fossils follows the
lithographical character of the rocks in which they occur. The Permian
structure in Kansas, as discovered and laid down by Prof. Swallow, is
generally recognized. It is to avoid confusion in the mind of the general
reader that these more specific and scientific divisions are not given the
prominence to which they would otherwise have valid claims. The Permian strata
of Kansas are, according to Prof. Swallow, 704 feet in thickness.
The deposits consist of limestones, clay shales, sandstones and, in the upper portions, gypsum and chert beds. In the lower strata, the limestones are more compact and uniform, and the chert beds less numerous. Some of the lime has been called magnesian, but analysis has failed to show, in more than a single instance, over five per cent of magnesia. In most strata, they afford, on being burned, a good quicklime. The shales, sometimes improperly called, slate and sometimes soapstone, are all in some degree composed of lime, so that of the whole deposit fully one-third is composed of that substance.
The strata of this period, like those of all before described, are nearly horizontal, but dipping slightly to the northwest, and are of nearly the same persistence and regularity over a large extent of the outcroppings. The exceptions to the tendency to dip to the northwest are distinctly to be seen in some instances. Thus the peculiar and clearly defined black shale, with its contiguous firm limestone, seen near the penitentiary south of Leavenworth, dips easterly and appears at the waters edge of the Missouri River, at Parkville. A similar instance occurs in the heavy bed of limestone in the bluffs in the southern part of Wyandotte County.
No metallic mineral, except poor iron, and that in small quantities, has yet been found in the area covered by the Upper Carboniferous, and the geological indications strongly discourage any attempt to search for them. The deposits are so clearly undisturbed, oceanic and sedimentary, that metallic substances cannot be expected.
The region as a whole shows only thin and occasional seams of poor coal. There are no coal outcrops upon the surface, and borings to the depth of more than five hundred feet have failed to reach good working seams of coal. In a general sense, like the Permian of Europe, it furnishes no coal, and is very properly termed by Prof. Mudge, barren carboniferous.