How many horses were in the 1955 Kentucky Derby?

1954 Kentucky Derby had a field of 17 horses:

Determine

Hasty Road

Hasseyampa

Goyamo

Admiral Porter

Correlation

Fisherman

James Session

Allied

Gov. Browning

Super Devil

Red Hannigan

Black Metal

Timely Tip

Sea O Erin

King Phalanx

Mel Leavitt

Determine was the winner; Hasty Road 2nd; Hasseyampa 3rd.