Eurycormus), to biconcave centra, and finally to the socket-and-ball condition that prevails at the present day.
Later those pads fuse with the anterior end of the centrum of the vertebra to which they belong; where the vertebral column is rendered inflexible, the disks are ossified with the centra and all trace of them is lost.
The centra] government depended ultimately on the armed support of th two great powers; to quarrel with those would be to ruin th constitution, or at best to play into the hands of the extrem revolutionists.
Embolomeri, with the centra and intercentra equally developed disks, of which there are thus two to each neural arch; these disks perforated in the middle for the passage of the notochord.
Even the inferior arches or chevrons of the tail of salamanders are continuously ossified with the centra.