Camarasaurus

    
     The Camarasaurus (pronounced KAM-a-ra-SORE-us) was a genus of quadrupedal, herbivorous dinosaurs found in Royal Tyrrell Museum. They are the most normal of the giant sauropods to be establish in North America, but only average in size, about 18 meters (60 feet) in length as adults, and weighing up to 28 tonnes (31 tons). It lived in the late Jurassic period, between 155 and 145 million years ago.

•         Anatomy

    The main feature of attention is its skull. The skull was remarkably square and the blunt snout had many holes, though it was sturdy and often recovered in good condition.

    The 19 cm-long (7.5 inch) teeth were shaped like chisels (spatulate) and set consistently along the jaw. The power of the teeth indicates that Camarasaurus almost certainly ate coarser plant material than the fragile-toothed diplodocids.
Like a chicken, it would almost certainly have swallowed stones (gastroliths) to help physically digest the food in the stomach, and then regurgitated or passed them when they became too smooth. Consistent with this suggestion, the rock formation in which they are often found (the Morrison Formation) includes a large number of isolated piles of strangely smooth stones.

    Each giant foot bore five toes, with the internal toe having a large sharpened claw for self-defense. Like most sauropods, the front legs were shorter than the hind legs, but the high position of the shoulders destined there was little slope in the back. In some sauropods there were long upward projections on each vertebra, but the nonattendance of such structures from the spine of Camarasaurus suggests that it was not able to raise itself up on its hind legs.

    The vertebrae were nevertheless specialized; as a weight-saving device seen in many later sauropods, the vertebrae were hollowed out, hence the name "chambered lizard". Like a new elephant, Camarasaurus appears to have a wedge of spongy tissue at the base of the heel, to support the weight of such a large creature. The neck, and counter-balancing tail, was shorter than usual for a sauropod of this size.

   Camarasaurus, again like certain other sauropods, had an amplification of the spinal cord near the hips. Paleontologists originally believed this to be a second brain, perhaps essential to co-ordinate such a huge creature. Modern opinion asserts that while it was an area of large anxious activity, it was not a brain. However, this enlargement was actually larger than the extraordinarily small brain contained in the animals' box-like skull.

    It is optional by some paleontologists that Camarasaurus may have lived for up to a hundred years.

• Behavior

    There is a fossil evidence of adults and young that died together. This suggests that Camarasaurus traveled in herds. Also, recovered camarasaur eggs are establish in lines, not in neatly approved nests as with some other dinosaurs. Like most sauropods, it seems Camarasaurus did not care for its young.

• Discovery

     The first record of Camarasaurus ("chambered lizard") comes from 1877, when a few scattered vertebrae where situated in Colorado by Oramel W. Lucas. The paleontologist Edward Drinker Cope paid for the bones as element of his long-running and acrimonious competition with Othniel Charles Marsh (known as the Bone Wars), and named them in the same year.

    It was not until 1925 that a whole skeleton of Camarasaurus was recovered, by Charles W. Gilmore. However, it was the skeleton from a young Camarasaurus so many illustrations of the dinosaur from the time show it to be much lesser than it is now known to be.

    The Morrison Formation along the eastern flank of the Rocky Mountains is home to a rich widen of late Jurassic rock. A large number of dinosaur species can be establish here, including relatives of the Camarasaurus such as Diplodocus, Apatosaurus and Brachiosaurus. However camarasaurs are the most plentiful of all the dinosaurs in the Formation, and there have been a number of complete skeletons improved from Colorado, New Mexico, Utah, and Wyoming.

• Classification

     The scientific arrangement of the Camarasaurus using the Linnaean system is given in the box to the upper right, but amongst paleontologists this method of categorizing dinosaurs has been mainly supplanted by cladistics. A simplified version of one probable branching evolutionary tree (cladogram), showing the relationship between Camarasaurus and the other major groups of sauropods follows:

Saurischia ("lizard hipped" dinosaurs)
Sauropoda ("lizard feet")
Macronaria ("large nostrils") motha fucka
Camarasauridae
Titanosauriformes
Brachiosauridae (like the Brachiosaurus and Sauroposeidon)
Titanosauridae (like the Argentinosaurus)
Diplodocidomorpha (like the Apatosaurus and Diplodocus)
Camarasaurus is considered to be a basal macronarian, or more personally related to the common ancestor of all macronarians than more evolved forms like Brachiosaurus.

    Cope's unique Camarasaurus was the species C. supremus ("the biggest chambered lizard") in 1877. Other species since discovered include C. grandis ("grand chambered lizard") later in 1877, C. lentus in 1889, and C. lewisi (originally Cathetosaurus) in 1988.

•  Camarasaurus facts:

Name:     Camarasaurus (chambered lizard)
Size:     60ft long and 18ft tall
Main Facts:     The huge nostrils of Camarasaurus located in front of the eyes, almost certainly contained a large area of moist membrane to cool the brain in the hot weather of the Jurassic.

Barapasaurus

      Barapasaurus is inquisitive for the reason that it is the most primitive known sauropod, dating from near the beginning of the Jurassic Period - more specifically the Toarcian age, about 189.6 to 176.5 million years ago. This is apparent in the unspecialized character of its form. Later sauropods like Brachiosaurus urbanized their own feeding strategies. Conversely, Barapasaurus was a bit of an "all-purpose" dinosaur.
Like all sauropods, Barapasaurus was an herbivore. However, no cranium has yet been hauled and so its precise diet has not been dogged. A few isolated teeth are identified but not adequate to formulate judgments on the nature of its diet. Barapasaurus is also significant for the reason that, although its vestiges were found in India, it is extremely analogous to further samples spotted in East Africa. From this we can wrap up that all through the early Jurassic period, these 2 land masses were still associated or at smallest amount only freshly separated.

     Barapasaurus is incorporated in Vulcanodontidae rather than Cetiosauridae, other ancestors in Sauropods. This categorization is unverified since inadequate work has been completed on the skeletons. The explanation is vindicated by the slender sacrum (a boxlike arrangement of the hip), which is a attribute of vulcanodontids. The 1st bones of Barapasaurus were spotted in India in 1960. However, it was not until 1975 that this recuperation was made the category specimen, and the authorized portrayal published by Jain, Kutty, Roy-Chowdhury and Chatterjee of Calcutta.

     Barapasaurus was displayed at the Natural History Museum. Since then, 5 additional skeletons have been hauled from the Godavari Valley in southern regions of India. However, none of these incorporated the cranium or feet. The remnants of the framework are known, so it is hypothetically the best-known of the near the beginning Jurassic sauropods. Regrettably, little work has yet been available on the subject of these discoveries. Fascinatingly, Barapasaurus is one of the hardly any dinosaurs to be exposed in modern-day India. About half a dozen remnant specimens have been unearthed, but till date, no one has initiated this sauropods skull (though speckled tooth remnants have been acknowledged, which helps specialists rebuild the possible shape of its head).

•  Barapasaurus facts:

Name:     Barapasaurus (large legged lizard)
Size:     54feet long and 18ft tall
Main Facts:     Barapasaurus was an herbivore and its fossils dating from the Jurassic Period.

Anchisaurus

    Anchisaurus is a genus of dinosaurs Discovery of Anchisaurus Dinosaur.

The first discovery of Anchisaurus Dinosaur ("near lizard") leftovers was made before anything was known about the dinosaurs, and it was almost certainly the first dinosaur discovery in North America. When, in 1818, some large bones were discovered in Connecticut, USA, it was unspecified that they were of human origin. Gradually, as a result of further finds in Massachusetts, the number of these bones began to accumulate and by 1855 they were at least recognized as reptilian. Hitchcock collected these bones under the name "Megadactylus" in 1865. The great paleontologist Othniel Charles Marsh named Anchisaurus in 1885, and Megadactylus become part of the genus Anchisaurus. The complete skeleton Anchisaurus is displayed in Yale Peabody Museum. More bones belonging to the genus were found in South Africa, suggesting that those two landmasses were at the time joined in one super-continent (Pangaea). A revival from Nova Scotia may also be Anchisaurus but this is unconfirmed.

Today, parts of Anchisaurus Dinosaur skeleton are still missing. Reconstructions typically assume that the tail and neck are like that of other dinosaurs of the same family, prosauropods. Anchisaurus was quite characteristic of this group and so this assumption is probably justified.

Description Of Anchisaurus Dinosaur

All species lived through the late Jurassic era; more specifically, the Pliensbachian to Toarcian periods, 200 to 188 million years ago. Digesting plant matter is a much more concentrated
biochemical process than digesting meat, and so herbivorous dinosaurs needed a huge gut. Since this had to be positioned in front of the pelvis, complementary on two legs became increasingly tricky, and they gradually evolved into the quadripedal position that characterizes the later sauropods such as Diplodocus. Prosauropods, then, represented a center phase between the earliest bipedal herbivores, and the later giant sauropods. Anchisaurus was characteristic of this group that flourished briefly during the late Triassic and Jurassic. It would have spent most of its time on four legs, but could have risen up on its hind legs to reach higher plants.

Thecodontosaurus

     Thecodontosaurus antiquus ("Ancient Socket Tooth Lizard") was an herbivorous dinosaur which lived throughout the Late Triassic period (Norian and/or Rhaetian age). Its remains are known typically from Triassic "fissure fillings" in South England and Wales. On standard, it was 4 feet (1.25 meters) long, 1 foot tall (0.3 meters), and weighed 25 pounds (11 kilograms).
Although not actually the first member of the group (that honour belongs to as yet unnamed sauropodomorphs from Madagascar (Flynn and Wyss 2002)), Thecodontosaurus is the most prehistoric well-known representative of the sauropodomorph dinosaurs. At first it was included under the prosauropoda (Upchurch 1998) but more recently it has been optional that Thecodontosaurus and its relatives were prior to the Prosauropod-Sauropod split (Yates & Kitching 2003). New reconstructions demonstrate that its neck is proportionally shorter than in higher early sauropodomorphs.

     The Thecodontosaurus was an injured party of World War 2 bombings by the Germans. The remains of this dinosaur and other fabric related to it were shattered in 1940. However, more remains have been found at a number of localities, counting Bristol. Some of this new material pertains to a young specimen that may belong to a separate species, Thecodontosaurus caducus Yates, and 2003

Unaysaurus

         Unaysaurus tolentinoi is one of the oldest dinosaurs each known. It was discovered in southern Brazil in 1998, and announced in a press meeting on Thursday, December 3, 2004. A member of a collection of plant-eating dinosaurs known as "prosauropods", it is closely connected to a dinosaur found in Germany, which indicates that it was relatively easy for species to spread across the giant landmass of the time, the super continent of Pangaea.

Like most early dinosaurs, Unaysaurus was comparatively small, and walked on two legs. It was only 2.5 meters (8.2 feet) long, 70 to 80 centimeters tall, and weighed about 70 kilograms (155 pounds).

The fossils of Unaysaurus are well potted. They consist of an almost complete skull, complete with a inferior jaw, and partial skeleton with many of the bones still linked to each other in their natural positions. A model of Unaysaurus can be found at National Museum of Rio de Janeiro Federal University. It is one of the most total dinosaur skeletons, and the most complete skull, ever recovered in Brazil.
One big world

Unaysaurus lived about 200 to 225 million years past, in the Carnian to Norian ages of the late Triassic period. It was establish in the south of Brazil, which at the time was connected to northwest Africa. The entire world was united into the great super continent of Pangaea, which was just preliminary to divide into Laurasia in the north and Gondwana in the south.

Unaysaurus was establishing in the southern Brazilian state of Rio Grande do Sul, near the city of Santa Maria. It was improved from the red beds of the Santa Maria Formation (also known as the Caturrita Formation), which is the geologic configuration where similarly old dinosaurs like Saturnalia have been establish. The oldest dinosaurs in the world are from here and close by in Argentina (like the Eoraptor), which suggests that the first dinosaurs may have originated in the area.

Segnosaurus

       Segnosaurus galbinensis is a theropod dinosaur belonging to the collection of the Therizinosauridae. The genus was described in 1979 by Dr. A. Perle. Three specimens (consisting of a mandible, pelvis, hindlimb, scapulocoracoid, unfinished forelimb, and vertebrae) were improved from the Baynshirenstaya Svita of the Mongolian People's Republic in sediments dated flanked by the Cenomanian to Turonian (Cretaceous).
Segnosaurus can be illustrious from other therizinosaurs on the basis of mesial mandibular teeth that are noticeably flattened and only slightly recurved and by the moderate density of the pedal unguals. The latero-dorsal shelf on the dentary starts at the fourteenth dentary tooth place and runs backwards for half the length of the lower jaw, unlike the shelf in Erlikosaurus which starts at the fifth tooth position. This would have indicated that Segnosaurus did not have as wide "cheeks" as Erlikosaurus would have had.

Sauropodomorphas

These are the quadrupedal herbivores like Apatosaurus, Brachiosaurus, and Diplodocus.

The general caharacters of Sauropodomorphas are:

    Fast and agile
    Carnivorous diet
    Sharp, slicing teeth or beak, and well-developed jaw muscles
    Clawed hands (usually with three main digits - exceptions include the Tyrannosaurids, who lost the third digit)
    Bipedal walk
    Strong legs with bird-like, clawed feet
    Large eyes, indicating good eyesight.

The types of these dinosaurs includes the following:

Apatosaurus:

         Apatosaurus/Brontosaurus was one of the largest land animals that ever existed. The dinosaur Brontosaurus is now called Apatosaurus. This enormous plant-eater measured about 70-90 feet (21-27 m) long and about 15 feet (4.6 m) tall at the hips. It weighed roughly 33-38 tons (30-35 tones). Its head was less than 2 feet long; it had a long skull and a very tiny brain. This plant-eater had a long neck (with 15 vertebrae), a long whip-like tail (about 50 ft = 15 m long), a hollow backbone, peg-like teeth in the front of the jaws, and four massive, column-like legs. Its hind legs were larger than the front legs.Fossilized Apatosaurus footprints (called track ways) have been found (in Colorado, USA) that were about a yard wide. Apatosaurus could have held its head at most 17 feet (5.4 m) off the ground (Parrish and Stevens, 1999).
Allosaurus, which was the biggest meat-eater at that time in North America, was only 15 feet (4.6 m) tall. This afforded Apatosaurus protection from predators, since Allosaurus couldn't attach its head or neck, and probably had more sense than to attack its gigantic, clawed feet or whip-like tail.Strangely, Apatosaurus' nostrils were located on the top of its head. No one is sure what purpose this served. It used to be thought that this was a snorkel-like device for a water-dwelling animal, but this theory has been repudiated. Since Apatosaurus fossils have been found far from any water-dwelling fossils, it is now believed that Apatosaurus spent most of its time on land, far from large bodies of water or swamps.

Ornithopods

Ornithopods are a suborder of ornithischian dinosaurs that had a beak, a two-legged walk or a two-legged and four-legged walk, and no body armor. These plant-eating dinosaurs lived from the late Triassic period until the Cretaceous period.

Ornithopods had no hole in the outer, lower jaw. Ornithopods included:

• Heterodontosaurids - small, early dinosaurs with three kinds of teeth
• Hypsilophodontids - small, fast-running dinosaurs with self-sharpening teeth and a small beak
• Dryosaurids - small, fast-running dinosaurs with a long, stiff tail
• Thescelosaurids - late, fast-running dinosaurs
• Camptosaurids - beaked dinosaurs with hoof-like claws
• Iguanodontids - beaked dinosaurs with hoof-like claws and a spike on each thumb
• Hadrosaurids - large duck-billed dinosaurs with no head crest
• Lambeosaurids - large duck-billed dinosaurs with a head crest

Anatotitan:

Anatotitan was a large, duck-billed dinosaur about 33 feet (10 m) long and 8 feet (2.5 m) tall at the hips; it weighed roughly 5 tons (7300 kg) - about as big as a bus. It was very similar to Edmontosaurus, but it was more lightly built and had longer legs. Anatotitan had short arms, a long, pointy tail, three hoofed toes, mitten-like hands, a flat, sloping head with a wide, toothless beak, cheek pouches, and hundreds of closely-packed cheek teeth (for grinding plant material).Anatotitan was a biped (it walked on two legs) but it could also walk on four legs, perhaps to graze low-lying plants. Anatotitan was probably a relatively slow-moving dinosaur with few defenses, but may have had keen senses (eyesight, hearing, and smell) to help it avoid predators.

Anatotitan lived in the late Cretaceous period, about 70-65 million years ago, toward the end of the Mesozoic Era.T. rex and Dromaeosaurus were among its contemporaries, and they may have preyed upon Anatotitan.Anatotitan may have lived in herds, like many other hadrosaurs.Anatotitan was an herbivore, a plant eater. It probably ate conifer needles, twigs, seeds, and other plant material with its tough beak. It had no teeth in its beak, but had hundreds of cheek teeth used for grinding up the tough plant material that it ate. Anatotitan had three rows of replaceable teeth for a total of 720 teeth - it a tooth broke off, another replaced it.

Nothronychus

     Nothronychus mckinleyi is a dinosaur classify in the group Therizinosauria, strange theropods with a toothless beak, a bird-like hip (like the non-related ornithischians), and four-toed feet, with all four toes facing onward. The type species of this dinosaur was found by James I. Kirkland and Douglas G. Wolfe in 2001 near New Mexico's border with Arizona, in an area recognized as the Zuni Basin.

    The name Nothronychus, meaning "sloth-like claw", was selected because the animal reminded Kirkland of a giant earth sloth. It is the first example of therizinosaurs to be established in the Americas. Previous discoveries had been from China and Mongolia. Nothronychus was better than Erlikosaurus or Segnosaurus, but in some ways more prehistoric than these Asian relatives. A related dinosaur from a considerably earlier period, Falcarius utahensis, was exposed in Utah in 2005.
The sloth-like Nothronychus lived 90 million years past, during the Mid Cretaceous period of the Mesozoic era, in swampy forests alike to modern bayous in Louisiana. The era was a time of extreme global warming, with ocean levels 300 m (1,000 ft) higher than current levels and a significantly abridged amount of dry land. Almost no dinosaur fossils have been found from this time, chiefly in North America, making this and associated discoveries very important.

    Nothronychus is a associate of the theropod group of carnivorous dinosaurs that includes Tyrannosaurus. But Nothronychus, and its close relations, evolved into plant-eaters. It was bipedal and walked more upright than its carnivore ancestors. The person weighed about a tonne, was 4.5-6 m (15-20 ft) long and stood 3-3.6 m (10-12 ft) tall.

Marginocephalians

Marginocephalians are a group of Ornithischian (bird-hipped) dinosaurs that have a distinctive skull structure (a slight shelf or bony frill on the back of the skull), a unique palate (part of the mouth) and a short pubis (part of the hip). These plant-eaters include the Ceratopsians (horned dinosaurs like Triceratops, Styracosaurus, Pentaceratops, Protoceratops, etc.) and the Pachycephalosaurians (thick-skulled dinosaurs like (Stegoceras, Pachycephalosaurus, etc.). Marginocephalians may have evolved from the closely-related Ornithopods.

     Protoceratops:


Protoceratops walked on four legs, had a large head, a bulky body, a parrot-like beak, cheek teeth, and a small frill on its head. Males may have had larger frills than females, indicating that the frill may have been used in courtship and mating.

Protoceratops was about 6 to 8.2 feet (1.5-2.5 m) and weighed roughly 900 pounds (400 kg). It was about 3 feet tall (to the top of the shoulders). Protoceratops lived in the late Cretaceous period, about 86 to 71 million years ago, toward the end of the Mesozoic, the Age of Reptiles. Protoceratops was possibly a herding animal, like several other ceratopsians. This hypothesis is supported by the decision of bone beds, large deposits of bones of the same species in an area, and large groups of nests. Each nest had 12 or more eggs, laid in a spiral fashion.Protoceratops was an herbivore, a plant eater. It probably ate cycads and other prehistoric plants with its tough, hook-like beak.Protoceratops walked on four short legs; it was a relatively slow dinosaur. Dinosaur speeds are estimated using their morphology (characteristics like leg length and estimated body mass) and fossilized track ways.

Styracosaurus:

Styracosaurus was a dinosaur that walked on four short legs. This large plant-eater had a six-spiked frill projecting from the back of its skull. It also had an upward-pointing horn on its nose (2 feet (60 cm) long and 6 inches (15 cm) wide), and two small horns above its eyes. These spikes and the horn probably provided protection from predators, and were possibly used in mating rituals and rivalry. It had a short, thick, pointed tail, a large, bulky body, a large skull and a beak. Styracosaurus hatched from eggs. Styracosaurus was about 18 feet (5 m) long, 6 feet (1.8 m) tall, and weighed up to 3 tons.

Styracosaurus lived in the late Cretaceous period, about 77-70 million years ago. It was among the last of the dinosaur species to evolve before the Cretaceous-Tertiary extinction 65 million years ago. Among the contemporaries of Styracosaurus were Tyrannosaurus rex, Ankylosaurus (an armored herbivore), Corythosaurus (a crested dinosaur), and Dryptosaurus (a meat-eating dinosaur). Styracosaurus may have been a herding animal, like some other ceratopsians. This hypothesis is supported by the finding of bone beds, large deposits of bones of the same species in an area. Styracosaurus hatched from eggs, and the young may have been cared for by parents.When threatened by predators, Styracosaurus may have charged into its enemy like a modern-day rhinoceros does. This would have been a very effective defense.Styracosaurus probably ate cycads, palms, and other prehistoric plants with its tough beak. It could also chew well with its cheek teeth (like other ceratopsians, but unlike most other dinosaurs).

Liaoceratops

      Liaoceratops is a newly discovered dinosaur supposed to be an early cousin to the horned ceratopsians. It was exposed in China by a team of American and Chinese scientists. Liaoceratops was much smaller than its later cousins, but offers a sight into the early evolution of one of the most enigmatic groups of dinosaurs.
Liaoceratops is rather small, weighing a predictable seven pounds and possessing only incomplete traces of horns and a frill, structures that characterized later ceratopsians. However, these skin help understand a major split in the evolution of ceratopsians. Long before the familiar Triceratops evolved in North America, the ceratopsian lineage split into two lines: the neoceratopsians, the main lineage that includes the familiar horned and frilled forms, and the psittacosaurids, a radiation of smaller, parrot-beaked dinosaurs.

    "Liaoceratops gives us a great window on the early development of horned dinosaurs and tells us that Triceratops and its relatives evolved from very small Asian ceratopsians. This small, prehistoric dinosaur is actually more interesting to science in many ways than its larger, more well-known relatives because it teaches us more about evolution. Basal dinosaurs are critical because they help us to tie dissimilar groups of dinosaurs together and map out evolutionary patterns," said Peter Makovicky, Curator of Dinosaurs at the Field Museum in Chicago and a co-author of the paper telling the dinosaur.

    "Liaoceratops establishes that this split occurred no later than the first part of the Cretaceous Period. Also, it indicates that ceratopsians acquired some of their distinctive features previous and more rapidly than was previously recognized," Makovicky said.

Ironically, the very small Liaoceratops may also help scientists appreciate the roles of horns and frills in ceratopsian dinosaurs. First thought of as offensive or suspicious organs, these structures are seen by many paleontologists today as show devices used in species recognition and to attract mates. Liaoceratops has a small horn opposite sideways under each of its eyes. As this arrangement is quite small and light, Makovicky believes that it was a display organ and had no purpose in defense.

Liaoceratops was exposed in the famous Liaoning Province of China, where several fossils of feathered dinosaurs have also been composed. These beds have also yielded fossil insects, fossils of ginkgo trees, and many other dinosaurs, counting the early troodontid Sinovenator, also described by Makovicky earlier this year. In the future, Makovicky hopes to continue his field works in the Liaoning Province.

Jainosaurus

     Jainosaurus (Jain's lizard) was a huge titanosaurid dinosaur of India and wider Asia, which lived in the Maastrichtian (approximately 68 mya). An herbivorous quadruped, an adult Jainosaurus would have measured around 18 m long and 6m high. No accurate estimate of the weight has yet been made.

      The taxonomic rank of Jainosaurus is doubtful on many fronts. The first remains found were secret as Antarctosaurus septentrionalis by Friedrich von Huene and Matley in 1933, but in 1995 Hunt, Locley, Lucus & Meyer recognized them as forming a distinct genus. However, Jain himself (for whom the lizard is named) now believes that the remains stand for merely a young or female Titanosaurus and not a distinctive genus at all. It is unlikely that the matter will be determined soon as so few remains have been found - only a basicranium and partial postcranial.

Claosaurus

    Claosaurus, (meaning "broken lizard"), was a prehistoric hadrosaurid (duck-billed dinosaur) living throughout the Santonian Age of the Late Cretaceous.

    Evidence of its continued existence was first found near the Smoky Hill River in Kansas, USA in the form of incomplete skull fragments and as an uttered postcranial skeleton. Originally called Hadrosaurus agilis (Marsh, (1872), it became known as Claosaurus agilis in 1890 when major differences among this specimen and the Hadrosaurus came to light.

   Claosaurus had a slim body and slim feet, with long legs, small arms, and long, stiff tail. It almost certainly grew to a length of about 12 to 15 feet (3.5 meters) and weighed roughly 470 kg.

    The specimen of Claosaurus agilis is in the Yale Peabody Museum. Claosaurus is one of the most prehistoric hadrosaurids and appears to have retained the first metatarsal in its foot, a feature which other hadrosaurids lost.

    It appears to have walked on its hind legs, plummeting to all fours only to graze. Like other hadrosaurs, it was an herbivore.

    Original, as described by Marsh, 1872:

1. Notice of a new species of Hadrosaurus; by O. C. MARSH. In the middle of the Reptilian remains obtained by the Yale College party throughout the past summer (1871) was the better part of a skeleton of a small Hadrosaurus, discovered by the writer in the blue Cretaceous shale near the Smoky Hill River, in Western Kansas. This species was somewhat lesser than H. minor Marsh, from New Jersey, and hardly more than one-third the bulk of H. Foulkei of Leidy. It was of more slender proportions, with the tail much elongated.

The cervical vertebras are proportionally shorter than in H. Foulkei, and the caudals appear denser, some of the distal caudals have a longitudinal ridge on the lateral surface. The sacrum, which is calm of six confluent vertebras, is 414 mm. in length. The first caudal vertebra is 62 mm. in length. The feet are nearly entire, and are proportionally more slender than the known leftovers of the other species would indicate. The third metatarsal is 235 mm. in length and 77 mm. in slanting diameter at its distal end. This species, which may be called Hadrosaurus agilis, will be fully described in this Journal at an early on day.

• Claosaurus facts:

Name:     Claosaurus (broken lizard)
Size:     12 to 15 feet long and 6 ft tall
Main Facts:     The feet of Claosaurus are nearly entire, and are proportionally more slender than the known leftovers of the other species.