It was surprising to me the multitude of differences I distinguished between them.

Oh, each was distinctly an individual--not merely in size and markings, strength, and speed of flight, and in the manner and fancy of flight and play, of dodge and dart, of wheel and swiftly repeat or wheel and reverse, of touch and go on the danger wall, or of feint the touch and alight elsewhere within the zone.

They were likewise sharply differentiated in the minutest shades of mentality and temperament.
I knew the nervous ones, the phlegmatic ones.

There was a little undersized one that would fly into real rages, sometimes with me, sometimes with its fellows.

Have you ever seen a colt or a calf throw up its heels and dash madly about the pasture from sheer excess of vitality and spirits?
Well, there was one fly--the keenest player of them all, by the way--who, when it had alighted three or four times in rapid succession on my taboo wall and succeeded each time in eluding the velvet- careful swoop of my hand, would grow so excited and jubilant that it would dart around and around my head at top speed, wheeling, veering, reversing, and always keeping within the limits of the narrow circle in which it celebrated its triumph over me.
Why, I could tell well in advance when any particular fly was making up its mind to begin to play.