| Answer | Crossword Clue |
|---|---|
| frustule | the shell of a class of algae |
| frustules | FRUSTULE, the shell of a class of algae |
| phycobilin | any of a class of red or blue-green pigments found in the red algae and cyanobacteria |
| phycobilins | PHYCOBILIN, any of a class of red or blue-green pigments found in the red algae and cyanobacteria |
| inarticulates | INARTICULATE, any of a class of brachiopods lacking a hinge connecting the two shell valves |
| inarticulate | not articulate also UNARTICULATE / any of a class of brachiopods lacking a hinge connecting the two shell valves |
