Sometimes raindrops fall through a layer of air below 0°C, the freezing point ofwater. As they fall, the raindrops freeze into solid particles of ice. Ice particles smaller than 5 millimeters in diameter are called sleet.
A species could be a mimic if it's colors are slightly off from the creature they're trying to mimick, or, upon closer inspection, have a different body shape than the creature they're trying to mimick.