Haemal spine
A haemal arch is a bony arch on the underside of a tail vertebra of a vertebrate.
The hole so formed is the haemal canal.
It sometimes has a haemal spine on.
The blood vessels to and from the tail run through the arch.
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Wikipedia
A haemal arch is a bony arch on the underside of a tail vertebra of a vertebrate.
The hole so formed is the haemal canal.
It sometimes has a haemal spine on.
The blood vessels to and from the tail run through the arch.