Eunice, which a very large force, having eighteen pieces of artillery, two of which are 20-pounder Parrotts, the rest 6 and 12 pounder pieces, mostly rifles. He has also four 24-pounder pieces on the way, which will probably be in to-day (20th instant). They are now on or near Bayou Clay, over which they are constructing bridges, intending to attack us about Choctaw Island and foot of Cypress Bend. Montgomery and Ross are said to be ready to co-operate on the Mississippi shore with twelve pieces of artillery. Colonel Greene is with Burbridge's command.

General Fagan had his headquarters at Monticello. He will probably be in to command the whole. Marmaduke was at Lake Village with ten or twelve pieces of artillery. Marmaduke left Lake Village Saturday, 18th instant, and has moved north. Couriers and pickets are constantly seen on the Arkansas bank. Burbridge has a large number of horses, mules, wagons, &c., and others coming in. Arms and ammunition said to be in abundance. Shelby has gone to Missouri. Kirby Smith still at Shreveport. These men state the enemy intend blockading the river as long as possible and then all go to Missouri. General Taylor is said to be on his way to join Marmaduke with quite a force. These paroled prisoners positively state the enemy intend trying to stop the navigation of the river between Columbus and head of Cypress Bend. I fell sure the information received from these men is reliable. If the enemy does come to the bank of the river, as he threatens, a military co-operation will be necessary to clear the river of him. I have only been able to hear that Murmaduke has about 1,000 men and Fagan 3,500.

I have the honor to be, general, your obedient servant,

E. K. OWEN,

Lieutenant Commander, U. S. N., Commanding 6th Dist., Miss. Sqdn.

[Indorsement.]

HDQRS. MILITARY DIVISION OF WEST MISSISSIPPI,
New Orleans, La., June 26, 1864.

Copy respectfully furnished for the information of Major-General Rosecrans, commanding Department of the Missouri.

Other information renders it improbable that General Dick Taylor is adding to Marmaduke's force. It cannot be ascertained that Marmaduke has more than Pratt's battery of six guns. The numbers of Marmaduke's, Shelby's, and Fagan's given correspond nearly with that reported by other informants.

By order of Major-General Canby:

ALBERT J. MYER,

Colonel, &c., U. S. Army.

HEADQUARTERS DEPARTMENT OF THE GULF,
New Orleans, June 20, 1864.

Commodore J. S. PALMER,

Commanding, &c.:

COMMODORE: The commanding general desires me to request of you the following information: What amount of naval force is there int he waters of Berwick Bay and those waters adjacent, and