The annual Dartmouth College Concert Series will open in Webster Hall on the evening of December 7 with the appearance of the National Symphony Orchestra from Washington, D. C. Hans Kindler will conduct the orchestra in its Hanover concert. The remainder of the series will include Kirsten Flagstad on January 18, the Salzburg Opera Guild on March 1, and the duo-pianists Luboshutz and Nemenoff on March 29.