I am studying Stravinsky's Rite of Spring (just for my own pleasure) and I have the Dover Miniature Score.
On the instrumentation page, I see entries such as these:
3 Flutes (Fl. III = Picc. II)
Alto Flute (G)
Is this saying that the third flautist will double with a piccolo? So, there may be a need for 3 flutes and 1 piccolo or 2 flutes and 2 piccolos but never 3 flutes and 2 piccolos. On the other hand, there should be a dedicated player for the alto flute.
There are similar entries for oboe and English horn, bassoon and contrabassoon, etc.
P.S. I have only surprisingly recently encountered the term "English horn". Despite being in England, I am much more used to "cor anglais".