LITERATURE CITED
- Ayala, F. J., and M. E. Gilpin. 1974. Gene frequency comparisons between taxa: support for the natural selection of polymorphisms. Proc. Natl. Acad. Sci. U.S.A. 71: 4847–4849.
- Berthet, P. 1964. Essai Biotaxinomique sur les Discomycètes. Dissertation, Université de Lyon.
- Borowsky, R. 1977. Detection of the effects of selection on protein polymorphisms in natural populations by means of a distance analysis. Evolution 31: 341–346.
- Clayton, J. W., and D. N. Tretiak. 1972. Aminecitrate buffers for pH control in starch gel electrophoresis. J. Fish. Res. Board Canad. 29: 1169–1172.
- Fries, E. M. 1822. Systema Mycologicum. Vol. 2. Lund and Greifswald. 238 p.
- Gessner, R. V., M. A. Romano, and R. W. Schultz. 1987. Allelic variation and segregation in Morchella deliciosa and M. esculenta. Mycologia 79: 683–687.
- Groves, J. W., and S. C. Hoare. 1953. The Helvellaceae of Ottawa District. Canad. Field-Naturalist 67: 95–102.
- Hervey, A. G., G. Bistis, and I. Leong. 1978. Cultural studies of single ascospore isolates of Morchella esculenta. Mycologia 70: 1269–1274.
- Hesler, L. R. 1960. Mushrooms of the Great Smokies. The University of Tennessee Press, Knoxville. 289 p.
- Jacobs, M. E. 1982. Beta alanine and tanning polymorphisms. Comp. Biochem. Physiol. B. Comp. Biochem. 72: 173–178.
- Markert, C. L., and I. Faulhaber. 1965. Lactate dehydrogenase isozyme patterns of fish. J. Exp. Zool. 159: 319–332.
- Nei, M. 1978. Estimation of average heterozygosity and genetic distance from a small sample of individuals. Genetics 89: 583–590.
- Overholts, L. O. 1934. The morels of Pennsylvania. Proc. Penn. Acad. Sci. 8: 108–114.
- Ower, R. 1982. Notes on the development of the morel ascocarp: Morchella esculenta. Mycologia 74: 142–144.
- Persoon, C. H. 1801. Synopsis Methodica Fungorum. Gottingen. 706 p.
- Poulik, M. D. 1957. Starch gel electrophoresis in a discontinuous system of buffers. Nature 180: 1477–1479.
- Romano, M. A., D. B. Ralin, S. I. Guttman, and J. H. Skillings. 1987. Parallel electromorph variation in the diploid-tetraploid gray treefrog complex. Amer. Nat. 130: 864–878.
- Seaver, F. J. 1928. The North American Cup-Fungi (Operculates). Seaver, New York. 284 p.
- Selander, R. K., M. H. Smith, S. Y. Young, W. E. Johnson, and J. B. Gentry. 1971. Biochemical polymorphism and systematics in the genus Peromyscus. I. Variation in the old-field mouse (Peromyscus polionotus). Univ. Texas Publ. 7103: 49–90.
- Shaw, C. R., and R. Prasad. 1970. Starch gel electrophoresis of enzymes—a compilation of recipes. Biochem. Genetics 4: 297–320.
- Smithies, O. 1955. Zone electrophoresis of starch gel: group variations in the serum proteins of normal human adults. Biochem. J. 61: 629–641.
- Sneath, P. H. A., and R. R. Sokal. 1973. Numerical Taxonomy. W. H. Freeman, San Francisco. 573 p.
- Swofford, D. L., and R. B. Selander. 1981. Biosys I: a FORTRAN program for the comprehensive analysis of electrophoretic data in population genetics and systematics. J. Heredity 72: 281–283.
- Ventenat, E. P. 1798. Dissertation sur le genre Phallus. Mem. l'Inst. Nat. Sci. Arts, Sci. Math. Phys. 1: 503–523.
- Volk, T. J., and T. J. Leonard. 1989. Experimental studies on the morel. I. Heterokaryon formation between monoascosporous strains of Morchella. Mycologia 81: 523–531.
- Weber, N. S. 1988. A Morel Hunter's Companion. Two Peninsula Press, Lansing, Michigan.
- Weber, N. S., and A. H. Smith. 1985. A Field Guide to Southern Mushrooms. The University of Michigan Press, Ann Arbor. 280 p.
- Wright, S. 1978. Evolution and the Genetics of Populations, vol. 4. Variability within and among Natural Populations. Univ. Chicago Press, Chicago. 580 p.