Lake Ontario Steam Boats..--At the last dates the boats had not commenced running, though the ice had left the river and several vessels from Sackett's Harbor had arrived at Ogdensburg. Last year the American steam boat Ontario, the Canadian boat Frontenac, and the Queenston, plied regularly through the season, between Niagara, Kingston, Ogdensburg, Prescott, &c.; and whether the number is to be this year increased, we are not yet informed. The steam boat Niagara, of Prescott, has commenced her regular trips on the Canada side of the St. Lawrence. The ice disappeared from the river at Montreal, as early as the 29th ult. and Durham boats arrived there from Sackett's Harbor on the 1st inst. This is said to be unusually early.