Istanbul, Turkey, March 28--Samuel Insull, flitting in phantom fashion about the labyrinthine waterways of the Near East, was reported proceeding through the Dardanelles today, bound for the Black Sea.

His grimy little Greek freighter, the Maiotis, on which the fugitive Chicagoan fled from Greece to escape return to the United States to face trial for fraud, passed the Turkish port of Chanak, on the Straits, where the ship was inspected by local officials.

The Turkish authorities planned to accompany the Maiotis through Turkish waters to prevent his making a secret landing.

It was generally believed here that Insuall now intends to proceed into the Black Sea, there to seek an isolated landing spot, possibly in Roumania