Pertica quadrifaria: Maine's State Fossil

Pertica quadrifaria is the scientific name of a primitive plant that lived about 390 million years ago during the Devonian Period. Its fossilized remains were discovered in 1968 in the rocks of the Trout Valley Formation in Baxter State Park near Mount Katahdin. Based on the type of rock it is found in today and the other fossils associated with it, Pertica quadrifaria grew in a brackish marsh near an active volcano. Fragments of the plants were preserved when they fell into the marsh and were covered by sediment before they could decay. After millions of years of burial, the plant remains are now exposed along eroding stream banks. The photo shows the central stem and several branches which terminate in sporangia (click on the photo for an enlarged view).

The plant illustrated at right is an artist's reconstruction of Pertica quadrifaria. It probably reached a maximum height of about six feet, making it the largest land plant at that time (Pertica is a Latin word meaning a "long pole or rod"). Its stem, which measured up to one inch in diameter, bore both sterile and fertile branches arranged in four rows which spiraled up the stem (quadrifaria means "in four ranks"). The fertile branches ended in dense clusters of sporangia, or spore cases, while the sterile branches subdivided to form forked tips. These forked ends may represent the first step in the evolution of leaves.

Pertica quadrifaria was selected as the Maine State Fossil for several reasons. It was first discovered in Maine. It is also a rare fossil; well-preserved remains of Pertica are found at only three other places in the world besides Maine. Finally, it is an important fossil scientifically as it represents a significant early step in the evolution of vascular land plants which ultimately resulted in numerous modern species, including the pine tree.

Important Note:

It is illegal to remove fossils or minerals from Baxter State Park. People caught with specimens in their possession will be prosecuted. Fossil specimens should be left where they are found for future park users to enjoy.

Last updated on October 6, 2005