Its strong belly originates near the shoulder joint from clavicle, coracoid and scapula.
In the fore-limb the clavicle and the radius and ulna are well developed, allowing of considerable freedom of motion of the fore-paw.
He has shown that, as in the Crossopterygian and Chondrostean ganoid fishes, there co., are two clavicular elements on each side; the lower corresponds to the clavicle of reptiles and higher vertebrates, whilst the upper corresponds to the clavicle of teleostean fishes, and has been named by him "cleithrum."
As stated above, there is strong evidence in favour of the view that some forms at least possessed in addition a "supracleithrum," corresponding to the supra-clavicle of bony fishes.
In most of the Caudata the scapular region alone ossifies, but in the Ecaudata the coracoid is bony and a clavicle is frequently developed over the praecoracoid car tilage.
- Scapula, coracoid and clavicle, meet to form the foramen triosseum, through which passes the tendon of the supracoracoideus, or subclavius muscle to the tuberculum superius of the humerus.