The trial heats in the interscholastic boat races will be rowed down stream this afternoon, beginning at 2.30, over a mile course which starts above Harvard bridge and finishes at the Union Boat Club. Owing to the bad weather and the early date of the races, ten days earlier than last year, the crews are not as far advanced as at the last races. The most promising of all the crews are Stone's, Noble and Greenough's, and English High School.

The winners of each heat and the winner of the race for second crews will enter the final race on Tuesday. The positions of the crews are as follows, beginning next the wall:

First heat--Brookline High, Boston Latin, Volkmann's, and Waltham High.

Second heat--Browne and Nichols, Cambridge High and Latin, Roxbury Latin, Chauncey Hall, and Hopkinson.

Third heat--Mechanics Arts High, English High, Noble & Greenough's, and Stone's.