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.
Canticum Sacrum him” . Canticum Sacrum Canticum Sacrum ad Honorem Sancti Marci Nominis is a 17-minute choral-orchestral piece composed in 1955 by Igor Stravinsky (1882–1971) in tribute "To the City of Venice, in praise of its Patron Saint, the Blessed Mark, Apostle." The piece is compact and stylistically varied, ranging from established neoclassical modes to experimental new techniques. The second movement, "Surge, Aquilo", represents Stravinsky's first movement based entirely on a tone row. Though most often abbreviated ""Canticum Sacrum"", the piece's full name is "Canticum Sacrum ad honorem Sancti Marci Nominis", or "Canticle to Honor the Name of Saint Mark". Stravinsky selected