1. Polydactyly is a type of polymelia where an organism has more than the usual number of digits on its limbs.
多趾症是一种多肢畸形的类型，指动物的肢体上有超过正常数量的数字。

2. The mutation caused the cat to develop polymelia, resulting in it having six legs instead of the usual four.
突变导致这只猫出现了多肢畸形，结果它的腿的数量变成了六个，而不是通常的四个。