Compared with the cocoons of other North American species, the cocoons of cecropia moths are enormous — up to four inches [10 cm] long and two inches [5 - 6 cm] wide.
Võrreldes teiste Põhja - Ameerika liblikate kookoniga, on Hyalophora cecropia oma tohutult suur, kuni 10 sentimeetrit pikk ja 5 – 6 sentimeetrit lai.