By H. Thompson Rich A swarm of huge, fiery ants, brood of a mystery comet, burst from their shells to threaten the unsuspecting world. Tokyo, June 10 (AP).—A number of the meteors that pelted Japan last night, as the earth passed through the tail of the Mystery Comet have been found and are puzzling astronomers everywhere. About the size of baseballs, orange in color, they appear to be of some unknown metal. So far, due to their extreme hardness, all attempts to analyze them have failed. Their u