Below that is a bone called the sacrum, which is attached to the pelvic bone on either side, called the ilium, and where they meet is the sacroiliac joint.
They extend from the cranium and sacrum where they start, out to the lungs or liver or bladder — wherever their effector is — where they reach their ganglion.
In the 1880s, Yale paleontologist O. C. Marsh found that some specimens of Stegosaurus had a big cavity in it sacrum, where the spinal column meets the pelvis.
1880 年代, 耶鲁古生物学家 O. C. Marsh 发现剑龙的一些标本其骶处有一个大空腔,也就是脊柱与盆的交汇处。
And some experts think that cavity in its sacrum was actually used to store glycogen, the starchy compound that animals -- including you and me -- use to store energy.
The sacrum is, in turn, also fused or attached to the ilium depending which animal you're looking at and this whole structure, of course, is designed to support the great weight of the Tyrannosaur.
The uterus is anchored to the sacrum by utero-sacral ligaments, to the anterior body wall by round ligaments, and it's supported laterally by cardinal ligaments as well as the mesometrium, which is part of the broad ligament.