Massachusetts' Senate heard a letter yesterday from Kirtley F. Mather, professor of Geology, denouncing the Sullivan Bill. The Senate is at present reviewing the proposal, which was passed by the House on Wednesday.

Mather, who wrote the letter in his capacity as chairman of the Massachusetts Civil Liberties Union, labeled the bill to prevent the "teaching of atheistic communism in Massachusetts schools and colleges" as "delightfully vague."

The letter decried the measure as a muzzle to all social sciences teachers. The vagueness of expression in H-422's text could conceivably be applied to Republicans as well as Communists, Mather claimed.

"For instance," the letter says, "both the Communist Party and the Republican Party favor an anti-poll tax law and housing laws." This would make Republican teachers liable for expulsion, a $300 fine, and jail.