"85 C.T.S. A 'winged' bird asleep"
"84 C.T.S. Collision in mid-air. 2 Cadets killed"
The crashed aircraft in the third photo is number C650. This collision happened on September 13th, 1917. The two airmen who died were Cadets James de Beaujeu Domville and Justin John Kramer.
Photos from an album that belonged to Christopher Paulus Devos, a sergeant in the Royal Flying Corps who was an instructor for 84 Canadian Training Squadron, based at Camp Mohawk, near Deseronto, Ontario.