from tip to tail. Another kind is smaller and paler, while the third has colorful spots on its sides. Biologists can distinguish the frogs by sound, but it's not easy for the layperson.
學生物的人還利用聲音來分辨，「每種蛙叫的聲音都有些不同，但要外行人藉此去辨識，確實不易。」