The foramen cordiforme (ischio-pubic fenestra) is a large space bounded by the pubes and ischia. In a number of lizards such as Hemidactylus (Mahendra, 1950), Uromastyx (El-Toubi, 1949) and Calotes (Iyer, 1942), it is divided by a ligament into right and left halves, but in Naultinus and Hoplodactylus such a ligament is lacking.

The epipubis is uncalcified in Naultinus but in the two species of Hoplodactylus examined it showed varying degrees of calcification. A metischial process (spina ischii) on each side is prominent in both genera. The prepubic (pectineal) processes are also well developed, especially in Naultinus. A ligament stretches from each prepubic process to the corresponding ischium, where it is fanned out to its attachment on to the ventral portion of this bone and on to the metischial process.

A hypoischium is present in all cases and its form is simple and rod-like, tapering behind. It remains an uncalcified cartilaginous structure in Naultinus.

In describing the os hypoischium, Camp (1923) lists the lizards in which it is absent. Among these he includes Hemidactylus, but Mahendra (1950) clearly shows that a small structure of this type is present.

Considerable controversy has occurred concerning the derivation of the os hypoischium. Camp (1923) considers that the hypoischium is only an “epiphysial calcareous deposition in the ligamentum hypoischium” rather than that it is a reduced primitive element (Mehnert, 1891). Camp points out that it is absent as far as is known in the extinct amphibians and reptiles. He also states that it is absent in Sphenodon, but Goodrich (1930, p. 201) shows a cartilaginous hypoischiatic process quite clearly in a diagram of the pelvic girdle of Sphenodon. Furthermore, Camp's statement that it is not represented in most primitive geckos does not seem to be a true generalisation now.