He said: "If they think I am mad enough to jump off at about 30mph, they must be barmy."
Explaining his unusual fall, he added: "What am I going to do, land on my head and make it look bad? I'm not going to make it look bad, I'm going to roll and look after myself."
The episode came as champion jockey Kieren Fallon was also suspended by the Jockey Club.
A stewards' ruling said that Fallon, 39, had failed properly to push his horse, Ballinger Ridge, to the finish line at Surrey's Lingfield course last week.
Fox allegedly leaped from the saddle minutes after a caller rang a newspaper at 2.30pm to say Ice Saint would not win in yesterday's 2.40 Cantor Sport Beginners' Chase at the Fontwell racecourse in Sussex. The caller warned: "Ice Saint is not going to win. Everyone has backed it to lose."
Odds on the horse - expected to start favourite - had drifted from 10-11 in overnight forecasts to as high as 6-1. The race was won by the 15-8 favourite, Honneur Fontenail.
Stewards suspended Fox from 19 March to 8 April after finding he had stepped off his mount in breach of rule 157. The Jockey Club will now probe betting patterns in the run-up to the race. Three gamblers bet against three other big-time punters through Betfair, an internet exchange site.
The trio staked £27,000, £34,000 and £37,000. So when horse and jockey parted company the three punters who offered the odds cleaned up.
The creation of internet betting exchanges has allowed gamblers to bet against a horse as well as on it. In effect, a punter betting against a horse is acting as a bookmaker as other punters take up the odds offered by that individual who is betting against the horse.
The Jockey Club dismissed further claims that it was currently investigating a widespread "betting scam" among jockeys.
