Flushing Trick = No More Pumping Your Septic Tank
http://probudds.buzz/8xw8wsrrGU-GLxFWEw-T8Cli-OTQfX5EQBKbAXDG5pQbpe47
http://probudds.buzz/j-H9qNZsuzNFvSkI6DXw_3N6GICkBGVSItrMdk7kpgIVgTR3
ve from three to five gill slits that do not contain actual gills. Usually no spiracle or true operculum is present, though many species have operculum-like structures. Instead of internal gills, they develop three feathery external gills that grow from the outer surface of the gill arches. Sometimes, adults retain these, but they usually disappear at metamorphosis. Examples of salamanders that retain their external gills upon reaching adulthood are the olm and the mudpuppy.
Still, some extinct tetrapod groups did retain true gills. A study on Archegosaurus demonstrates that it had internal gills like true fish.
Invertebrates
A live sea slug, Pleurobranchaea meckelii: The gill (or ctenidium) is visible in this view of the right-hand side of the animal. Crustaceans, molluscs, and some aquatic insects have tufted gills or plate-like structures on the surfaces of their bodies. Gills of various types and designs, simple or more elaborate, have evolved independently in the past, even among the same class of animals. The segments of polychaete worms bear parapodia many of which carry gills. Sponges lack specialised respiratory structures, and the whole of the animal acts as a gill as water is dra