Linda Hardy, 43, who received severe head injuries during the assault nine days ago, has recovered sufficiently to give detectives a description of the man.
Two women discovered Mrs Hardy crawling through undergrowth at Chipperfield Common, near Hemel Hempstead, Hertfordshire. Surgeons at the Royal Free Hospital, London, said that she had suffered a fractured skull and had a broken jaw, nose and cheek bones.
Mrs Hardy yesterday described her attacker as a young, stockily built white man, clean shaven with dark brown, short hair. He wore a short-sleeved shirt and dark trousers.
A spokesman for Hertfordshire police said that Mrs Hardy told police she was beaten with a gun 'of some sort'.
Initially police were uncertain of any possible motive for the attack as there had been no evidence of sexual assault and none of her belongings were stolen. After speaking to Mrs Hardy, they said the motive for the assault appeared to have been sexual, but that Mrs Hardy put up a considerable struggle and the attack was unsuccessful. The man was either injured or blood-splattered, the spokesman added. Detectives are anxious to eliminate the driver of a car or van parked in the area before the attack at 9.45am.