Amphibia (the amphibians) is a class of vertebrate animals, which in their early life breathe by gills or branchiae, and afterwards partly or entirely by lungs. The Frog, breathing in its tadpole state by gills and afterwards throwing off these organs and breathing entirely by lungs in its adult state, is an example of the latter phase of amphibian existence. The Proteus of the underground caves of Central Europe exemplifies forms in which the gills of early life are retained throughout life, and in which lungs are developed in addition to the gills. A second character of this group consists in the presence of two occipital condyles, or processes by means of which the skull articulates with the spine or vertebral column; Reptiles possessing one condyle only. The class is divided into four orders: the Ophiomorpha (or serpentiform), represented by the Blind-worms, in which limbs are wanting and the body is snake-like ; the Urodela or Tailed Amphibians, including the Newts, Proteus, Siren, etc; theAnoura, or Tailless Amphibia, represented by the Frogs and Toads; and the Labyrinthodontia, which includes the extinct forms known as Labyrinthodons. Research Amphibia
Tragulidae is the mousedeer family of animals of the order Artiodactyla. Usually solitary and nocturnal, tragulids live in dense vegetation on the forest floor where they feed principally on grasses, leaves, and some fruit, but they also eat invertebrates, small mammals, and sometimes carrion. Limbs, are long and slender and end in hoofs. The carpals are cuboidal and highly specialized; the lateral digits are present although not strongly developed, and they are sometimes digitigrade. The hind feet have a cannon bone; the third and fourth metacarpals of the forefeet are either unfused (as in the African species) or only partially fused (as in the Asian species). An ossified plate to which the sacral vertebrae attach is present. Antlers and horns are absent. A postorbital bar is present. There is no sagittal crest, and the mandibular condyle is long. A full set of lower incisors is present, but the uppers are replaced by a horny pad. Canines are present, large and curved in males, extending below the lower lip, smaller in females. Research Tragulidae
The anconeus is a small triangular muscle that originates just below the elbow joint at the lateral condyle of the humerus and extends a fourth of the way down the forearm to insert in the olecranon process and back of the ulna. It is located on the outer back corner of the elbow. The anconeus is innervated by the radial nerve and supplied by the radial artery. It extends and stabilizes the elbow joint. Research Anconeus
The anterior meniscofemoral ligament extends from the inside of the lateral condyle of the femur, near the anterior cruciate ligament, across to the medial meniscus. This connection provides some of the lateral support for the knee in flexion and extension. Research Anterior Meniscofemoral Ligament
In anatomy, a condyle is a protuberance on the end of a bone serving to form an articulation with another bone:
more especially the term condyle is applied to the prominence of the occipital bone for articulation with the spine. Research Condyle
The anterior and posterior cruciate ligaments connect the inner surfaces of the head of the femur with the head of the tibia. They are so named because they cross each other, with the anterior ligament extending from the inside of the lateral condyle of the femur to the medial side of the tibial head, and the posterior ligament extending from the inside of the medial condyle of the femur to the lateral side of the tibial head. Research Cruciate Ligaments
The long, thin extensor digitorum longus muscle actually consists of four combined bellies and their tendons. The belly arises from the lateral condyle of the tibia and the front edge of the fibula and extends about three-fourths of the way down the lower leg. The four tendons lie close to each other and appear as one tendon that continues down to the front of the ankle. When the tendons reach the back of the foot they separate and extend to the middle and distalphalanges (bones) of the toes two through five. The muscle is innervated by deep branches of the peroneal nerves and supplied by branches of the anterior tibial artery. The
extensor digitorum longus extends the toes (separates the toes) and bends the foot toward the leg. The tendons may clearly be seen on the top of the foot when the toes are extended. Research Extensor Digitorum Longus
The flexor carpi ulnaris is used to bend the hand at the wrist. It gets its name from carpus (wrist bone) and the ulna (forearm bone). This muscle has two heads, one originates from the medial condyle of the humerus and the other originates from the olecranon and upper border of the ulna (forearm bone). The two heads combine to form a single, flat belly that tapers into a long tendon inserting in the pisiform bone of the wrist. It is innervated by the ulnar nerve and supplied by the ulnar artery. This muscle lies along the ulnar side of the forearm and works with the extensor carpi ulnaris to bend the hand at the wrist. If it continues to contract, it bends the elbow. Research Flexor Carpi Ulnaris
The gastrocnemius muscle extends the length of the leg from the knee joint to the ankle joint. It consists of a lateral head (caput laterale), a medial head (caput mediale), and their single tendon of insertion. Each head is a thick muscular column, separated from the other by the back of the knee. As they descend, they come together. The medial head is larger and originates from the medial condyle of the femur. It wraps around the leg more towards the front than does the lateral head. The lateral head originates from the lateral condyle of the femur. The muscular heads end at or slightly above the middle of the leg, where they attach to their tendon. The two heads form the bulging 'belly' of the calf of the leg. Their tendon descends and fuses with the tendon of the soleus, which lies just beneath it, forming the Achillestendon, which inserts in the calcaneus. The gastrocnemius muscle is innervated by the tibial nerve and supplied by the tibial artery. This muscle propels the body when walking, running, or jumping. It raises the heel, which lifts the body. It also assists, though minimally, in flexing the knee joint. Research Gastrocnemius
The iliotibial tract, also called the iliotibial band, is a long, wide, band of fascia that lies over the muscles on the outer surface of the thigh. It begins superiorly at the level of the greater trochanter of the femur (upper edge of the thighbone) and ends inferiorly where it inserts in the condyle of the tibia. This band is a thickening of the normal fascia that surrounds the entire leg. It is thin medially (inner thigh), but is thick laterally (outer thigh). Acting almost like a ligament, this tendon helps mainly to stabilize the knee joint, but also acts in flexing (bending) and extending (straightening) the knee. Research Iliotibial Tract
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Amphibia
