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Amphibians This group includes frogs, toads, salamanders etc. They resemble the fishes especially the lung fishes. The modern amphibians are essentially fishes in their early life when they are tadpoles; later legs sprout the tail becomes absorbed and lungs take the place of gills. Judging from these facts, we may assume that fish like ancestors from the development of lungs became fitted for life on land and that from these the amphibians of today have been derived. The most interesting of our amphibians in Colorado, is the tiger salamander. In the east this species drops its gills in early live and assumes the adult form, but in the cold waters of Colorado and neighboring states it may never become adult, but always retain its gills. The peculiar thing in their life history is that these immature salamanders breed in their immature state. They are locally known by the name of Axolotl and we commonlly call water dogs, mud puppies etc.
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Reptilia Among the lowest reptiles are the lizards; we have one common little lizard in Colorado known as a sand swift. Here belong the snakes which have the peculiarity of being able to swallow prey of a size greater than the normal size of its own body, this they can do becuase the lower jaw is separated from the upper jaw by a bone, known as the quadratus. As snakes grow they shed their skin; in the case of the rattlers the skin on the end of the tail is not cast off, but remains as a horny remant known as a rattler. The skin of snakes is frequently shed in August; as the skin drys it becomes opake over the eyes so that the snakes vision is obscured and they are said "to go blind," at this season they strike at the least provocation. Another representative of this group is the turtle, it has two skeletons, an endo skeleton and an into skeleton. The word tortoise is commonly applied to land and fresh water species, while marine forms are generally called turtles, but by many writers the words are used synonimously.
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Turtles are provided with horny jaws, but they have no teeth. The exoskeleton appears to have been developed on account of the fact that these animals need protection from various materials floating down the streams in which they live.
Some turtles have the front or back of the lower exoskeleton hinged so that they are capable of drawing in their head, legs and tail, then completely closing up the exoskeleton; these are known as box turtles.
In the crocodiles and aligatorys the body is covered with an armor of bony scales. They procure their prey many times by grasping and pulling it under the water and thus drowning it. They themselves do not drownd because the nose and ears and throat are provided with valves to keep out the water when the animal goes under.
An aligatore two feet long is aproximently fifteen years old; one twele feet long may be reasonably supposed to be seventy five years old.
Both aligators and crocodiles lay eggs in the sand and depend upon the suns heat to hatch them.
The horn toads also belong to the reptilia; they are therefore not toads since toads belong to the amphibia. They are perfectly harmless and
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easily tamed, but it is said that when irritated They sometimes preform the remarbible feat of spurting a stream of blood from the eyes, toward the intruder for a distance of several inches. There is one very interesting thing about [am] horntoads, they possess on the forehead a [pinmial] eye.
There is but one poisonous lizard known and that is the gilia monsters, found in Arizona, New Mexico, and Mexico in the hot desert regions
The reptilia are very suseptible to cold and when the temperature lowers they rapidly grow and less and less active. When winter comes on they seck protected spots [and] either alone or in groups, together they hibernate. In this condition the various activities of the body are at a very low [ebb]. The blood barely circulates, breathing is barely suseptible, and stiff and insensible to the world about them they remain until the warmth again stirs them to their forms activity. At such times no food is token, but owing to their low in weight it is probable that a slow consumption of the supplies the small amount of [nemicary] energy. When the turtles hibernate they go far down into the mud.