John R. Wagner, until three weeks ago a freshman at M.I.T., was arrested in Oklahoma City early Saturday morning for robbing an Illinois bank of $19,000. Wagner had eluded a police search for three and a half months.

The arrest abruptly halted Wagner's lavish cross-country spree, in which he used up all but $4,575 of the original sum. Among other things, Wagner was reported to have spent more than $1800 on call girls during the last five days of his freedom.

Police stated that on Aug. 28, Wagner, unassisted, had looted the State Bank of Richmond, Ill. He then escaped in a car stolen "from a man's garage in Chicago," and headed for Cambridge.

Questioned about his crime, Wagner said, "It was just to be the one robbery and no more. I felt guilty because my parents were going to send me to this very expensive college, and I knew they couldn't afford it and would have to make sacrifices."

Only Wanted $2500

"All I wanted was enough to last me one school year, about $2500. I didn't know it would be so darn much more than I needed. That's the reason I started spending it like I did. I just threw it around and picked up the tab for everyone. I didn't like to see other students spending money they had grubbed for on frivolous things."

According to an official statement issued by John T. Rule, Dean of Students at M.I.T., Wagner drew attention to himself by the "prodigality" of his spending. His roommates and friends. however, were unavailable to supply details.

Aside from his lavish living habits, Wagner seems to have left little mark on the M.I.T. campus. His Math instructor, for instance, knew him only as a name on the role who had "done miserably" on two quizzes and thereafter failed to attend class.

M.I.T. students and faculty yesterday wondered how Wagner was ever admitted to the university. As one concerned undergraduate put it, "They could conceivably have let in Willie Sutton."