Florida stallion Notebook, whose son Booklet was Florida's 2002 Horse of the Year and whose daughter Spoken Fur is on the verge of a $2-million bonus, was euthanized Aug. 4 because of a ruptured stomach lining. The 18-year-old syndicated stallion, who stood for $15,000, was found in distress in his paddock at Michael O'Farrell's Ocala Stud Farm two hours after being let out yesterday. He was taken to Peterson & Smith Equine Hospital near Ocala and was put down shortly after the operation began due to the severity of the rupture.Notebook, who was a New York-bred champion racehorse for the late Eugene Klein, sired 35 stakes winners, including several grade I winners. Booklet, who also was Florida's champion 3-year-old male last year, captured the Fountain of Youth Stakes (gr. I), and Spoken Fur has won this year's Coaching Club American Oaks (gr. I) and the Mother Goose Stakes (gr. I). A $2-million bonus awaits her owner if she captures the Aug. 16 Alabama Stakes (gr. I) at Saratoga.Notebook also is the sire of earlier grade I winners Delaware Township and Three Ring, plus grade II winners Scratch Pad, Post It, and Summer Note.Bred by Eaton and Thorne, Notebook (Well Decorated -- Mobcap, by Tom Rolfe) posted impressive overall numbers as a stallion. He sired 78% starters from foals and 62% winners, plus the earners of $27.8 million. He covered 62 mares this year, and ended up getting a "good number in foal," according to farm manager Bob Noble. Notebook's book was limited the past four breeding seasons because of laminitis. As a racehorse, Notebook captured eight of 21 starts and earned $584,630 while trained by D. Wayne Lukas.