Sacrum lumbar vertebra, and its lower part with the coccyx (tailbone) via the sacral and coccygeal cornua. The sacrum has three different surfaces which are shaped to accommodate surrounding pelvic structures. Overall it is concave (curved upon itself). The base of the sacrum, the broadest and uppermost part, is tilted forward as the sacral promontory internally. The central part is curved outward toward the posterior, allowing greater room for the pelvic cavity. In all other quadrupedal vertebrates, the pelvic vertebrae undergo a similar developmental process to form a sacrum in the adult, even while the bony tail (caudal) vertebrae remain unfused.
Ver sacrum of the Roman people ("iussu populi"), then he specified a long series of unfavourable events and circumstances which were as a rule regarded as invalidating but would not be so as far as the present "votum" was concerned in the case they happen. The overall authenticity of the formula preserved in Livy's passage has been noticed by Dumézil while the exceptional theological and juridical prudence showed by Lentulus in ensuring that both fraud and ignorance of private citizens would not affect the validity of the "sacrum" and harm the Roman people has been remarked by Bouché-Leclercq. Ver sacrum Ver sacrum