Genal caeca of agnostids

GENAL cæca are lateral appendages of the stomach of trilobites and are interpreted as hepatic glands. These glands are not fossilized but are preserved as delicate imprints of veins in the trilobite test. Genal cæca have been found in many trilobites, especially in Cambrian ptychopariids. In agnostids, however, genal cæca have not been described as yet.