lake on rafts in considerable force, succeeded, on the 22nd instant, in surprising and capturing the small garrison of Brashear - although as fully warned of their danger as any orders could warn them - taking at the same time about 300 prisoners, two 30-pounder Parrott and six 24-pounder guns, a small train of cars, and everything else at the place.

Early yesterday morning Donaldsonville, garrisoned by but 225 men, including convalescents, under the command of Major J. D. Bullen, Twenty-eight Maine, was attacked by a large force of the enemy, under the command of Brigadier General Thomas Green, of Texas.

The attack began at 1.30 a.m., and lasted till daylight. The defense was most gallant. The brave garrison defended their interior line with desperation, and finally repulsed the enemy with great slaughter,killing and wounding more than their own number, and taking prisoners twice as many officers and nearly as many men as they had.

The enemy retreated some 5 miles, and General Green sent in a flag asking permission to bury his dead, singularly enough accompanied by an apology for his failure - that he was unfortunate in not getting his men into the skirmish, owing to the rashness of his commanders.

I sent down Brigadier-General --- last night will the First Louisiana Volunteers and two sections of Closson's battery, and General Emory sent up two companies from New Orleans.

The gunboats Winnona, Princess Royal, and Monongahela rendered great assistance in the defense of Donaldsonville, and they have since been joined by the Genesee.

Our forces on the railway have fallen back upon Algiers. The forces of the enemy now occupying the La Fourche and operating upon our communications consist of all the troops in Western Louisiana, under Major-General Taylor, and about 5,000 cavalry, sent by Magruder from Texas. Their whole force is from 9,000 to 12,000. The fall of Port Hudson will enable us to settle that affair very speedily.

The dispositions of Brigadier-General Emory were well made and with the greatest promptitude, and our only misfortune at Brashear is due entirely to the carelessness and disobedience of subordinate.

In these operations but 400 soldiers could be left in New Orleans to protect the depots of this army and all our vital interests in a large city occupied by a population essentially hostile, and liable, from its position, to sudden attacks from several quarters.

The consequences that would have followed the movement of the enemy upon the La Foruche, had my command moved to Vicksburg, leaving Port Hudson and its garrison in my rear, are obvious - New Orleans would have fallen. A few more days must decide the fate of this place. I regard its fall as certain.

Our losses in the attack were as follows:

Officer and men. Killed. Wounded. Missing. Total.

May 27: 15 90 2 107

Officers

Men 278 1,455 155 1,888

Total 293 1,545 157 1,995

June 14: 21 72 6 69

Officers

Men 182 1,245 180 1,607

Total 203 1,401 188 1,805