Dolphin Books

Doubleday Expanding Paperback Program in 1960, PW, Dec. 28, 1959, at 47 (announcing that Doubleday will supplement its existing paperback lines with a new one, not to replace Anchor, Image, or the Science Study series, with 50 titles to be on sale June 24, 1960). 

Doubleday Expanding Paperback Program in 1960, PW, Dec. 28, 1959, at 47, 48:

Within the Dolphin line there will be an important sub-series, Dolphin Masters. Dolphin Masters will reproduce authoritative texts of notable works, perhaps rare, hard-to-obtain first editions, or editions with significant textual features. These books are being set by the compositors directly from the original sources. Dolphin Masters (and some of the regular Dolphin Books, too) will often include facsimile original title pages.

Ad, PW, Mar. 21, 1960, at 8-9 (two-page spread listing the first 50 titles in the series and indicating the price as $.95 each, with "a few" at $1.45). 

Ad, PW, June 27, 1960, at 40 (listing the next 50 titles in the series for September 23, 1960)

The ad also announced a new subseries of Dolphin Books, the Dolphin Reference Series, with CR1, Poems to Remember, edited by John Kieran, and CR2, 100 Great Operas and Their Stories, by Henry W. Simon, each at $1.45. These two titles on issue were instead given the numbers C99 and C100, respectively, and styled with the words "A Doubleday Dolphin Reference Book" at the top of their front covers. 

Mike Shatzkin, A New Perspective on Some Old Family Publishing History, SHATZKIN FILES (May 10, 2009), https://www.idealog.com/blog/a-new-perspective-on-some-old-family-publishing-history/:

My father, Leonard Shatzkin, had created the Dolphin Books imprint at Doubleday in the late 1950s. Jason Epstein had gotten Doubleday into the “quality paperback” business early when he founded Anchor Books in about 1953. Len was “Director of Research” (that’s another story) at that time, with a big focus on strengthening the sales organization. He did so largely through a 1950s version of “automation” (which required a large roomful of worker bees at Doubleday’s plant in Garden City): a vendor-managed inventory plan that wrote the orders for the stores based on physical inventory counts the Doubleday reps sent from the accounts (instead  of orders!) 

In 1957 or 1958, they put 800 stores on the Doubleday Merchandising Plan. Backlist sales quadrupled. Cost of sales quartered (they had added a lot of sales reps, so travel expenses were cut sharply.) They wanted more books! 

But the Doubleday editorial department said, “there really aren't any more books. We see all the books that are made available; we buy the ones that are worth publishing.” So management created a new imprint, called Dolphin Books, and it reported to Len. 

Tom McCormack, later the dynamic CEO that built St. Martin’s from a relatively insignificant player importing Macmillan UK titles to an industry powerhouse, was a young editor there at that time. Dad had Tom start making lists of all the public domain books and what editions were available of them. As I heard the story (and Tom may read this and correct me), Tom said to Len: “I get it; we’ll figure out which books haven’t been done and do those.” To which Len said, “No. We have the strong sales force. We pick the ones that everybody does, because those are the ones that sell [no BookScan back then; no B&N or Amazon either]. We’ll push somebody else off the shelf.”

Anyhow, Dolphin was a big success.