Books: HIGGLEDY PIGGLEDY

New light-verse forms are as rare as septuplets, and as vulnerable. Latest in the long line of poetic inventions—and, it is to be hoped, not too vulnerable—is the double dactyl, the result of a collaboration of two poet-professors, Anthony Hecht of Bard College and John Hollander of Hunter. According to the rules set forth in Jiggery-Pokery (112 pages; Atheneum; $3.95), all the poems must begin with a double-dactyl nonsense line such as "higgledy-piggledy" or "jiggery-pokery." Thereafter comes a famous name—also double dac tylic—followed by another double dactyl and a line of four beats....