What is tube on driver side of engine

[Scutch]

Hello,

What is this tube that runs along the plugs side of the engine and has little tubes that go into the head right near each plug? Then it eventually connects to a vacuum line on my carbs.

That pipe has a crack and is blowing air. I assume is is some EGR thing.

Can that split in the pipe cause anything other than a loss of pollution?

This is an 1968 automatic 230s.

Thanks
Eddie