The Life Cycle Of A Monarch Butterfly Is Really Amazing. That's Why I Have A Page All About It! Monarchs Start Out In A Tiny Seed. 3 - 4 Days Later, They Hatch Out Of Their Egg. At That Time, It Is A Larva Or A Caterpillar. That Is The Only Stage They Do Their Growing. When They Are A Larva, It Eats Its Eggshell. When It's Done With Its Eggshell, It Moves On To The Plant It Was Layed On. Which Would Probably Be Milkweed. Monarchs Stay As A Larva For About 10 - 14 Days. The Next Stage Is The Pupa (Otherwise Known As A Chrysalis). This Is The Stage When Babies Are Transformed Into Adults. The Butterflies Stay In The Pupa For 10 - 14 Days. The Next (And Last) Stage Is The Adult. This Is The Stage When The Monarch Butterflies Find Mates. They Will Mate With Several Butterflies. You Can Tell A Male And Female Monarch Apart Very Easily. Males Have A Black Dot On Each Bottom Vein, While Females Don't. Later On, The Female Monarchs Lay Their Eggs On A Milkweed Plant. They Lay About 100 - 300 Eggs! After That, Sadly, They Die. Then The Egg Hatches, And The Life Cycle Goes Over Again!