| Answer | Crossword Clue |
|---|---|
| TEST | Invertebrate shell |
| SEASLUG | Shell-less marine invertebrate |
| WORM | Invertebrate |
| INSECTS | Invertebrate animals. |
| MARINEWORM | Ocean invertebrate |
| INSECT | Invertebrate creature |
| INSECT | Small invertebrate animal. |
| GIANTSQUID | The largest invertebrate |
| ARACHNID | Eight-legged invertebrate |
| TRILOBITE | Marine invertebrate of yore |
| OCTOPUS | Invertebrate with three hearts |
| CORAL | Invertebrate in some endangered structures |
| LAMARCK | Naturalist who coined the term "invertebrate" |
| SILURIAN | Period in which early invertebrate land animals appeared |
