This image shows a posterior view of the skeleton of a bullfrog. Aspects of the vertebral column and pelvic girdle that are visible include the first cervical vertebra that is called the atlas (1), the sacral vertebra whose transverse processes form the sacrum (2), the ilium (3), the ischium (4) and the urostyle (5).   As shown in the image, each hind limb is composed of a stout femur (6) and tibiofibula (7), two tarsal bones called the calcaneus (8) and the astragalus (9), the metatarsals (10) and distal bony elements called phalanges (11).   The suprascapula (12) and scapula (13) of the pectoral girdle are visible as well as the humerus (14) of each the forelimb.