Three longitudinal muscle bands which run the length of the colon (large intestine). They are named for their attachments on the transverse colon: tenia omentalis (located at the line of attachment of the greater omentum), tenia mesocolica (located at the line of attachment of the transverse mesocolon), tenia libera ("free" tenia - it has no mesenteric attachment obscuring it).
Sources:
http://www.uthscsa.edu/anatomy/Glossary.html
http://www.med.umich.edu/lrc/coursepages/M1/anatomy/peritoneum_tables.html