Egg-Laying Mammal
This page is the CodyCross answer for the clue below from Prehistory, Group 1242, Puzzle 4 (Geologic Time Scale).
Question is: Egg-Laying Mammal
and the answer is: MONOTREME
Word Meaning:
MONOTREME — (zoology) Any of the order Monotremata of mammals that lay eggs and have single orifices for urogenital and digestive functions (cloaca); an echidna, platypus or one of their extinct relatives.
Definitions from Wiktionary.