Washington, July 29. Lietit. Rogéis, oí tlie U. tí. staamer HuDtsville, reports that on the 6th, off A buco Ittland, he full in with tho Briti.sli schoener Agnes, of Nassau, from Ilurbor Island, without papers. He sent her to Key West for adjudicatioiï. A later report from tho snme officer says that on July 21st he hud captured tho rebel steamer Reliance, just out irom Dobay Bar, Georgia, and bound o Nassau, with two hundred and thirty-fonr bales Sea Island cotton. Tho Et'liancü was commanded by Lieut, Gladdiug, formoily of the U. d. ííav.