title: Chlorophyll derivatives in middle eocene sediments.
abstract: Chloroform extracts of middle Eocene brown coal were made; the chlorophyll derivatives obtained were separated chromatographically. The visible light spectrum, chromatographic behavior, HCl number, infrared spectrum, and mass spectrum of one of the pigments extracted is indicative of methyl pheophorbide a. This is the oldest occurrence of fossil phorbins reported.
authors.forename: D L
authors.initials: DL
authors.lastname: Dilcher
authors.forename: R J
authors.initials: RJ
authors.lastname: Pavlick
authors.forename: J
authors.initials: J
authors.lastname: Mitchell