Tube mermaids!

Partial tube-girl example
Two enter, one leaves

Our mermaids are indeed different. They’re made by mad scientsts in tubes!

Mad scientists made mermaids in tubes!>

Found at the tumblr Pulp Cover Art.

Afterthought: The title of the pulp graced by this illustration appears to be Terror Tales, but what if what is being depicted is a brewing process involving captive mermaids? Could it be Terror Ales?