What was the first SciFi work that had a an intelligent race that was biologically significantly different from humans?
Not simply "non humanoid", but, say, non-vertebrate (non-humanoid vertebrates are OK, as long as they are clearly non-humanoid). In other words, intelligent Octopii or better yet aliens like bacteria or insects; these are what I'm interested in, but intelligent cats - like Kzinti who are fairly humanoid - are not.
A "race" means there's a whole large population of biologically similar beings. One-off intelligent monsters like Chthulu or Godzilla aren't what I'm asking about.