Freshwater Bryozoa

A book about freshwater bryozoa? First because these are commonly found but forgotten beauties of freshwater ecosystem like natural lakes rivers ponds as well as all man-made reservoirs. They are very easy to find lovely to watch and highly interesting to study. They are very frequently or most of the time ignored. They are good indicators of water quality. They are filter feeders and purify water 24X7. They are huge nuisance to municipality and farmers as they choke up pipelines. They hold back huge amount of secrets about multi cellular organization. They are found on almost all types of substrata. They are having a unique relationship with sponge.