What feature gives the egg masses their characteristic name, leading to the common name 'spongy moth'?

Answer

The pale, felt-like, or 'spongy' layer of hair covering them

The name 'spongy moth' is derived from the appearance of the egg masses, which are covered in a spongy-looking layer of hair shed from the female's abdomen.

What feature gives the egg masses their characteristic name, leading to the common name 'spongy moth'?
insectmothlarvafactDefoliator