Since he has yellow legs and a single comb, maybe a Columbian Rock?
I found this on Cackle's website. Their Columbian Rock chicks look just yours did.
http://www.cacklehatchery.com/page%20247.htm
The black chick with the white spot on the head will be barred. The yellow chick with the black stripe down the back is feathering in with a juvenile partridge type pattern. No idea what breed.