*The pelvic girdle is a duplex structure like pectoral girdle which is made up of three cartilage bones in each half which are known as ossa innominata. *Each os innominatum is formed by three bones *These cartilage bones are – ilium, ischium and pubic. *Dermal bones are lacking in pelvic girdle. *The pelvic girdle has a depression (concavity) at the junction of the three bones which is known as acetabulum, into which the head of femur of the hind limb articulates. …show more content…
26.21 Pelvic girdle of Polypterus (A) and Lampanyctus (B) in ventral view Sarcopterygians – *The lobe-finned fishes were the first vertebrates to tend towards to venture on the land. *So, in them, the development of pelvic girdle becomes very important to support body weight in the transition from water to land. *In chonate fishes pelvic girdle (Fig. 26.22) consists of bilateral elements having a forward pubic process, a medial ischial process and a dorsolateral projecting iliac process. *In dipnoi the two parts are fused in the midline. *In this it resembles the pelvic girdle of amphibian and the beginning of the tetrapod walking