Before Dies Committee. Washington, D.C., Dec. 1. The Dies Committee Investigating un-American activities today questioned Joseph P. Lash, Executive Secretary of the American Students' Union, and Miss Agnes Reynolds, College Secretary of the Union. Lash testified that he was a member of the Socialist Party from 1929 to 1937. He said he resigned because he believed that the Socialist Party was subordinating the interests of the people of a whole to the interests of factional strife