Horse racing as a passion, as a heritage, as a fast buck is the impetus of these eighteen selections; some are fiction, some are non-fiction, many are a toss-up in the realm of race track recollection. Only two rank as literature--John Marquand's ""What's It Get You"" and Donn Byrne's long, feeling Tale of a Gypsy Horse--a few are overfamiliar--Lincoln Steffens' disenchantment at ""The Sporting Age,"" selections from National Velvet and Ben Hur: and a couple are curiosities--Mrs. General Custer's account of her husband and fellow-officers racing mules, a first-hand report of a Grand National steeplechase. Mostly it's the horse who comes through against odds (or doesn't come through because there are no odds) and much of it is told in Kentucky Southern like it was around the stables some years back, with a few real clinkers. (In one, ""The Look of Eagles,"" a Negro who is ""black as a buzzard,"" rolls ""the whites of his eyes"" and extends ""a black paw with a pinkish palm;"" in ""Hot or Cold,"" ""the infield, thronged with darkies, looked like a pan of ginger snaps."") If you don't object to this, it's an acceptable collection for track-wise kids, less so for romantic horse fanciers.