Across
- 2. have a pouch
- 3. humans dogs birds and fish
- 5. Fir on their bodies
- 7. cartilage and teeth in water
- 9. nourish the baby in the mother
- 11. skeletons inside the body
- 12. fir and lays eggs (two species)
- 13. feathered bodies
Down
- 1. bony fish
- 4. live in and out of water
- 6. dry scaly skin
- 8. generate their own heat
- 10. jaw jawless fish