Heightened activity in the Military Science Department with a 50 percent increase in the enrollment of the R. C. T. C. will result from the new national defense program, Arthur R. Harris, Lieutenant Colonel U. S. A. and professor of Military Science and Tactics, announced yesterday.

From 400 to 450 men will be able to take Military Science next year, depending on the number and type of students who apply, Harris said. 297 men are now studying R. O. T. C. courses a jump of 50 percent over last year.

So far an urgent request by Harris for one additional officer to handle the large number of men in his department next year has not been acted upon by college and military authorities.

The Naval Science Department, which is limited to 200 men by federal law, will have no such increase in the enrollment, C. H. J. Keppler, captain of the U. S. Navy and professor in Naval Science and Tactics, stated yesterday, Congress has authorized R. O. t. C. units to be established at two new universities, but it has not changed the Harvard Unit, he explained.