31. It lives among the external gills of its neotenous host, only occasionally straying from this hiding place during darkness. 32. Damselfly nymphs breathe through external gills on the abdomen, while dragonfly nymphs respire through an organ in their rectum. 33. The embryos develop a placenta after around four months of gestation, when they still possess vestiges of external gills . 34. Branchiosaurids like " Branchiosaurus " and " Apateon " are represented by many fossils preserving skin and external gills . 35. Their fully aquatic larvae are branchiate, with three pairs of external gills behind their heads and above their gill slits. 36. At an embryonic length of, the external gills have all but disappeared, and a covering of small denticles is present. 37. Instead of internal gills, they develop three feathery external gills that grow from the outer surface of the gill arches. 38. The tadpoles, which resemble fish fry but are distinguished by their feathery external gills , hatch out in about three weeks. 39. All the amphibians that returned permanently to the water developed external gills , feathery tissue that extends out from the body. 40. It is one to two inches long, with a slender body and external gills , and is a reddish-brown in color.
