Gee whilikers! Just shows how stanzas from any song that fits the meter (and some that don't) are added by performers and callers to fill out the dance.

Rear (pronounced r'ar) back, chicken is correct. In dance calls, this means stretch back (bend back, head up, arms up), imitating a horse rearing, before you go forward in the next move. Rare is one pronunciation of r'ar, but 'rare' is a mistake by the collector- should be r'ar.