What a howl! Anyone hung up on gallows humor will go for this collection of verses, limericks and tombstone toppers. Not precisely ""poems,"" they are just the sort of word-playing that youngsters can enjoy without groaning. The vague divisions seem more like pauses for some grisly Raskin illustrations; although many selections are certain draws, the caliber varies from relatively bland to genuinely weird. Dorothy Parker's lamenting ""Resume"" still stands up as does Thomas Hood's slightly askew ""Faithless Nelly Gray: A Pathetic Ballad"" in which Ben Battle (dis)figures: ""a cannon-ball took off his legs,/ So he laid down his arms!"" We're torn between a take-off of a master featuring the maiden Cannibalee (Lummis' ""Poe-em of Passion"") and Tierney's ""Donne Redone"" to a turn: ""Ask not for whom the bells toll./ Don't get yourself in a stew./ As long as you can hear the clang,/ Relax; they're not for you."" They're light enough to leave_you laughing, strange enough to keep you looking.