Answer:
Glossopteris and Mesosaurus are the two fossils that were initially used to support the continental drift theory.
Step-by-step explanation:
The continental drift theory, now widely accepted, had a lot of troubles to breakthrough at the beginning. The majority of the scientists found such a proposal preposterous, so the scientists that were pushing through this theory had to come up with very numerous and very hard evidence. One of the pieces of evidence were the fossils.
The two fossils that were initially used to support this theory were the Glossopteris and Mesosaurus. Both of these fossils were found in multiple continents that are now separated by ocean waters and are very far away from each other, and it is pretty much impossible that an organism is totally the same at two different locations, or to remain in the same form with the same characteristics in different environments. Glossopteris is actually a species of seed fern that was widely spread, while Mesosaurus is a freshwater crocodile-like reptilian.