Colletids are a diverse group of bees united by their nest building behavior: they line their nests with a thin, waterproof lining akin to cellophane, polyester, or silk. Otherwise, the two genera of colletids in the northeast–Colletes and Hylaeus–could not be more different. Colletes are about 3/4 the size of a honey bee, hairy, have a “cute” face due to convergent eyes, and nest underground. In contrast, Hylaeus are smaller than a grain of rice, hairless, predominately black, and nest above ground.