MARCH 19TH.—Mr. MacCubbin, whom I take to be a sort of Scotch-Irishman, though reared in the mobs of Baltimore, I am informed has given some passports, already signed, to some of his friends. This interference will produce a rupture between Capt. Godwin and Capt. MacCubbin; but as the former is a Virginian, he may have the worst of it in the bear fight.