Havana, May 7.-The steamer Triumfo arrived here last night, bringing the Cuban Gen. Goicouria under a strong guard of naval officers. Goicouria was immediately taken to the jail, where a "verbal" court-martial was assembled for the purpose of trying him. The court sentenced him to be garroted, and he was then placed in the capilla. At 4 o'clock this morning he was taken to Principe Fort, and at 8 o'clock garroted. An immense concourse of persons assembled on the Heights of Principe. The General remained perfectly serene and firm to the last.