The book is Opportunities in Pharmacy Careers (published in 2004, Revised Edition is what I have, if that makes a difference) by Fred B. Gable. It states (p. 41):
Pharmaceutical educators have adopted a jargon that differentiates doctor of pharmacy degrees according to the manner in which they were earned. Pharm.D. degrees earned as first and only professional degrees, via completion of "straight thru" curricula of two years of prepharmacy and four years of professional courses, are referred to as Pharm.D.1 degrees. Pharm.D. degrees earned as postbaccalaureate degrees, via completion of additional study as prescribed by a pharmacy school, are referred to as Pharm.D. 2 degrees.