racy Caulkins, the winningest swimmer in U.S. history, tonight added her fourth gold medal of the United States Swimming Short Course Championships by winning the 100-yard breaststroke in 1:02.41.

It was the 39th individual national title of her career. The versatile University of Florida freshman also earned the 200 and 400 individual medleys and the 200 backstroke titles here.

Dave Bottom managed the only record breaking of this final session. Bottom, swimming for the Walnut Creek (Calif.) Aquabears, toppled both the American and the U.S. Open 100-yard backstroke records of 49.08 held by Clay Britt of Rockville, Md. Bottom won in 48.94. Britt, a junior at the University of Texas, swimming for the Longhorns, finished fourth tonight in 50.0.

David Roach of the Starlit Aquatic Club in Fairfax, Va., finished seventh in the consolation heat in 51.42.

Steve Lundquist, a junior at Southern Methodist, won the men's 100 breaststroke final in 53.84 seconds. Jeff Kostoff, 16, of Industry Hills, Calif., captured his third title of the meet in the mile. Swimming in his first senior nationals, Kostoff became the second-fastest miler in U.S. history with a 14:52.39 finish. Earlier Kostoff won the 500-yard freestyle and set a U.S. record in the 1,000 freestyle.

The women's 100-yard backstroke was taken by 16-year-old Debbie Risen of the the Kansas City Blazers in 55.49. Theresa Andrews of the North Baltimore Aquatic Club was third in 56.57. Susan O'Brien of Starlit was seventh in the consolation in 58.07.

Jill Sterkel of the Longhorns successfully defended her 100-yard butterfly title. Sterkel won the final in 53.20, just .02 seconds ahead of runner-up Mary T. Meagher of Lakeside, Calif.

The 100 butterfly consolation was won by Starlit's Susie Rapp in 55.25. Rockville's Grace Whitis was fourth in 56.00.

The men's 100-yard butterfly title was claimed by David Cowell of Mid Ohio Valley YMCA, in 47.89. Andrew Wrenn of Starlit finished seventh in 49.33.