Hindu academics and experts, I need your help?

I'm writing an essay and I've just remembered I've missed an important point. I'm pretty sure that I read in the Purusha Sukta hymn that from Purusha's sacrifice, aside from the Caste system and the aspects of existence being created from his body parts, the meter for Hindu hymns was also created. I can't seem to find the reference, and I've tried to find it so this will be my last attempt for today: can any of you tell me whether this is true? Or is the origin of the hymn meter accredited to another legend? Thanks.