1. Clegg, M.T., Learn, G.H., and Golenberg, E.M. (1990) Molecular evolution of chloroplast DNA. In: Evolution at the Molecular Level (eds. R.K. Selander, A.G. Clark, and T.S. Whittam), Sinauer Associates, Sunderland, MA.
2. Church, G.M., and Gilbert, W. (1984) Genomic sequencing. Proc. Natl. Acad. Sci. USA 81, 1991–1995.
3. Cronquist, A. (1981) An Integrated System of Classification of Flowering Plants. Columbia University Press, New York.
4. Doebley, J., Durbin, M.L., Golenberg, E.M., Clegg, M.T., and Ma, D.P. (1990) Evolutionary analysis of the large subunit of carboxylase (rbcL) nucleotide sequence among the grasses (Gramineae). Evolution 44, 1097–1108.
5. Downie, S.R., Olmstead, R.G., Zurawski, G., Soltis, D.E., Soltis, P.S., Watson, J.C., and Palmer, J.D. (1991) Six independent losses of the chloroplast DNA rpl2 intron in dicotyledons: molecular and phylogenetic implications. Evolution, in press.