Book II Chapter 12

In birds, on the other hand, there are no ears, but only the auditory passages. This is because their skin is hard and because they have feathers instead of hairs, so that they have not got the proper material for the formation of ears. Exactly the same is the case with such oviparous quadrupeds as are clad with scaly¹ plates, and the same explanation applies to them. There is also one of the viviparous quadrupeds, namely the seal, that has no ears but only the auditory passages. The explanation of this is that the seal, though a quadruped, is a quadruped of stunted² formation.

1 scaly   

adj.鱼鳞状的；干燥粗糙的

参考例句：

• Reptiles possess a scaly,dry skin.爬行类具有覆盖着鳞片的干燥皮肤。
• The iron pipe is scaly with rust.铁管子因为生锈一片片剥落了。

2 stunted   

adj.矮小的；发育迟缓的

参考例句：

• the stunted lives of children deprived of education 未受教育的孩子所过的局限生活
• But the landed oligarchy had stunted the country's democratic development for generations. 但是好几代以来土地寡头的统治阻碍了这个国家民主的发展。