The Cope's grey treefrog ("Hyla chrysoscelis") is a species of tree frogs. They live in the United States. It is believed that the Cope's Grey Tree Frog evolved after the last major ice age. Cope's Grey Tree Frog can live in temperatures as low as -8 °C. Females can lay up to 10–40 eggs. The eggs hatch in four days. When the eggs hatch, they are called "tadpoles". Tadpoles will become a young frog in 45–65 days. The species name "chrysoscelis" is from the Greek word "chrysos", which means "gold". The Greek word "scelis" means "leg".