Dalton, the barometer of sales in this segment of book marketing. Books from both series make regular appearances on the Young Adult Bestseller list of B. In April 'The Hardy Boys Casefiles' were reopened. A year ago the updated 'Nancy Drew Files' began to appear.

The new Bobbsey Twins series follows on the heels of two other revivals within the last 12 months by Pocket Books. Carefree, happy and charming, they were forever heading off in the family car to a vacation in the North Woods or someplace, where the twins would be able to unravel some mild but titillating mystery. He lived in the real world of work, but money troubles never darkened the Bobbseys' world. Richard Bobbsey, the father, owned a lumberyard.

One enormous attraction - at a time when the Depression was still a reality in many people's lives - was the economic situation of the Bobbsey family. The stories took place in an archetypal American town called Lakeport. I distinctly remember devouring them as late as the seventh grade, just before moving on to Ulysses and The Waste Land. I am chagrined to discover from the publicity material issued by Pocket Books about the new project that the original Bobbsey Twins books were aimed at an audience of second- and third-graders. NEXT MONTH, Pocket Books (the mass-market paperback arm of Simon and Schuster) will issue The Secret of Jungle Park, the first volume in a series called 'The New Bobbsey Twins.' Of the panoply of children's adventure stories available when I was in elementary school in the 1940s, the Bobbsey Twins books were my favorites.

Monkey on a Stick by John Hubner