TELEGRAPHICJefferson City,Sept. 18—11 p.m. Two courienr just arrived from Lexing tun. The following intelligence is believed to 1-3 in the main part reliable : Geu. Price commenced an attack on the eu-11 trencaments at Lexington, commanded by iCcl. Mulligan, on Monday. The fighl ' had been renewed on T uesday morning by ; Gen. Price, but feebly When the couriers left Gen. Luue was at Johnston, Bate? county, on Monday morning. fire#from 2,000 to 3,000, marching to the relief ol Lexington. The rebel loss ou Monday is roporte 1 at 4,000, and that of out troops at 800, which ig probably exagger* atcd.Jefferson C/ty, £«pt. 18.Monday afternoon Gen. Price sent word to Col. Mulligan at Lexington, demanding his surrender. Col Mulligan's reply was to go to li —11. An attack was immedi, ately made by first opening with nrtilery t making an advene under its cover on tl«t town. Gen. Price was repulsed ith heavy loss.Gen. Lane, -%ith an estimated furcd of* 5,000 Kansas troops, is reported to bewttli* in 40 miles of Lexington, and arc rapidly advancing to reinforce Cul Mulligan — O ther Federal troops arc rapidly con verging‘from St. Joseph and other point* to reinforce Col. Mulligan. The 22nd# 24th* j and 2tith Indiana regiments have gone via steamer to., Lexiijgtpm Also: the foroaa-ser.tjr^u St.; Louis por the Pemoiocn and White*Cldoif. “ Thfte reinforccmeuta dud« her about 6,000 effective troops, and will1 i«ek lxmmglm ter wmw mdHrin# the IMtedtatfV: cenddene^ isfdk hare lime* Gel* Mulligan will he nttado fcoU- Lawing. ton until reinfcrwoient* arrive.