Denise-I have a book published in 1985 called Mammals and Their Milk, by Lucia Anderson. The publisher is Dodd, Mead & Co., 79 Madison Ave, N.Y. Also, there is a little table in Ruth Lawrence's book with some specifics about some animal milks. The book I have is a children's book, by the way, so isn't terribly detailed, but I don't know if that's what you're looking for. I spoke for one period to a 7th grade health class, and I started with species'specificity. I think that's a great way to get into the subject.