G.A.
I agree it is cradle cap. For my daughter we had to put baby oil on her head and leave it for a while then take a baby comb and keep going through her hair... it helps pull up the yellow stuff but it does not hurt the baby. Also combing the hair after a good bath helps too.
I like the advise to use a tooth brush. Although, you do not want a soft tooth brush... you want one that is medium or hard... because you want to work the scaling off.