1. After two months, the embryo measures long and has well-developed external gills . 2. They go through paedomorphosis and retain their external gills , thus resembling axolotls. 3. They are viviparous animals, giving birth to young that possess external gills . 4. The salamander has blood-red external gills for absorbing oxygen from the water. 5. Most other species have external gills , often associated with the parapodia. 6. The balancers eventually fall off and their external gills grow larger. 7. Four gill slits lined with gill rakers are hidden underneath the external gills . 8. When the embryo is long, the external gills are resorbed and pigmentation develops. 9. The larvae have external gills , and live in seepage areas until they metamorphose. 10. Small external gills adapted for small stream living can be found on their larvae.