Conjoined infant girls who share a lower spine and intestines will fly to Saudi Arabia later this month for possible separation surgery sponsored by Crown Prince Abdullah Bin Abdul-Aziz, the Deputy Premier and Commander of the National Guard, the twins' mother said yesterday. Thirteen-month-old Daria and Olga Kolacz will fly with their mother on Dec. 12 to Riyadh for tests to determine whether surgeons at the King Abdul Aziz Medical City for National Guard can go ahead with the complex operation, said Wieslawa Dabrowska, the mother. "This must end in success," Dabrowska, a 38-year-old seamstress, said in a telephone interview from her home in the central Polish town of Janikowo. She said Crown Prince Abdullah had offered to pay all of the family's medical and travel expenses after being informed of the case by a Saudi doctor. "It was a total surprise, but a very good one," Dabrowska said. The doctor learned of the infants' plight from a discussion forum on the Internet, said Dabrowska's nephew, Robert Kasznia. The Saudi Ambassador to Poland, Osama Al-Sanosi, said that the operation would be the sixth of its kind at the Riyadh hospital. "Whenever there is a complicated case like this one and our doctors are contacted by family members, they take the case to Crown Prince Abdullah, who is interested and is known for his generosity," Al-Sanosi said.