更多placoid例句

1. The tail is asymmetrical (heterocercal), and numerous placoid scales (dermal denticles) are embedded in the skin.
2. They pass by quite insensible gradations into normal placoid scales, such as cover the general surface of the body.
3. In some cases the placoid scales are enlarged to form plates or spines capped or coated with enamel.
4. The Thornback Skate is covered with prickles (placoid scales).
5. The teeth of Selachii are fundamentally identical with placoid scales.