Appeal by employer-carrier from a decision granting and allowing death benefits to claimant. Decedent died March 14, 1956, from postoperative peritonitis resulting from a radical gastroenterostomy, the board finding it to be a natural and unavoidable result of accidental injuries sustained on September 23, 1955. The sole question concerns the causal relationship between accident and death. A serious issue of fact developed from the medical testimony which the Referee resolved in favor of the claimant. Thereafter, the board, upon review and at the request of the carrier and in the interests of justice, decided the question of causal relationship should be submitted to an impartial specialist for an opinion. Dr. Crohn, the impartial specialist, reported in his opinion “ that the active ulcer which led to his death followed the trauma and was caused by the trauma of the accident which occurred on September 23, 1955”. He thereafter testified. Appellants now complain as to Dr. Crohn and state in their 'brief that the doctor’s testimony justified a contrary conclusion. Such an opinion is based upon facts, which are exclusively within the province of the board, assuming there is substantial evidence, which we find in this ease. (Matter of Palmero v. Gallucci & Sons, 6 A D 2d 911, affd. 5 N V 2d 5291.) Decision and award unanimously affirmed, with costs to the Workmen’s Compensation Board against the appellants. Present — Foster, P. J., Bergan, Coon, Herlihy and Reynolds, JJ.