Advertisement

The Botanical Review

, Volume 49, Issue 1, pp 65–115 | Cite as

Distribution and biohistory of the endemic flora of the mid-Appalachian shale barrens

  • Carl S. Keener
Article

Abstract

The mid-Appalachian shale barrens, first described by E. S. Steele in 1911, range within the eastern United States from south-central Pennsylvania to southwestern Virginia and adjacent West Virginia. These Paleozoic shaly outcrops are characterized by a steep southern exposure, typically an undercutting stream at the base, and a relatively sparse vegetation cover in contrast to the surrounding woodlands of the eastern deciduous forest. Lithologically, the barrens have thin, fissile, variously colored shale and siltstone fragments intermixed with sandstones and minor conglomerates. At least some of the barrens were colonizable sites since the late Tertiary. The sparsity of herbaceous vegetation is due chiefly to high insolation temperatures and low moisture conditions at the surface of the barrens, two physical parameters which eliminate most young seedlings. In addition to adapting to these severe constraints, the shale barren endemics require adequate root space, and, as obligate heliophytes, high sunlight intensity. Eighteen taxa are recognized as endemic to the shale barren region. Two (Phlox buckleyi, Trifolium virginicum) are paleoendemics, seven (Allium oxyphilum, Arabis serotina, Astragalus distortus var.distortus, Aster schistosus, Clematis coactilis, C. viticaulis, Solidago arguta var.harrisii) are neoschizoendemics with restricted ranges, six (Calystegia spithamaea ssp.purshiana, Clematis albicoma, Eriogonum allenii, Paronychia montana, Pseudotaenidia montana, Senecio antennariifolius) are holoschizoendemics, two (Antennaria virginica, Oenothera argillicola) are patroendemics which are ancestral to two or more species, and one (Helianthus laevigatus) is an apoendemic polyploid derivative. Possibly as many as six taxa (Antennaria virginica, Astragalus distortus var.distortus, Clematis albicoma, Eriogonum allenii, Oenothera argillicola, Senecio antennariifolius) are disjunct endemics with the vicariad in mid-central to western North America. The eighteen endemics are not equally distributed throughout the shale barren region, a fact which may reflect unequal evolutionary age, dissemination, and breeding structure. In general, speciation of the endemics appears to be largely an initial migration (from the southwestern United States) and geographic isolation of diploid populations or ecotypic differentiation of subsets of adjacent species within the Appalachian forests. Conservation of these endemics is strongly recommended.

Keywords

Chromosome Number Botanical Review North American Species Serpentine Soil Paronychia 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Literature Cited

  1. Allard, H. A. andE. C. Leonard. 1946. Shale-barren associations on Massanutten Mountain, Virginia. Castanea11: 71–124.Google Scholar
  2. Antonovics, J. 1971. The effects of a heterogeneous environment on the genetics of natural populations. Amer. Sci.59: 593–599.PubMedGoogle Scholar
  3. Artz, L. 1935. Plants of the Massanutten Mountains. Claytonia2: 4–5.Google Scholar
  4. —. 1937. Plants of the shale banks of the Massanutten Mountains of Virginia. Claytonia3: 45–50; 4: 10–15.Google Scholar
  5. —. 1948. Plants of the shale barrens of the tributaries of the James River in Virginia. Castanea13: 141–145.Google Scholar
  6. Barkley, T. M. 1978.Senecio. N. Amer. Fl. II.10: 50–139.Google Scholar
  7. —. 1980. Taxonomic notes onSenecio tomentosus and its allies (Asteraceae). Brittonia32: 291–308.Google Scholar
  8. Barneby, R. C. 1964. Atlas of North AmericanAstragalus. Mem. New York Bot. Gard.13(pt. II): 597–1188.Google Scholar
  9. Baskin, C. C. andJ. M. Baskin. 1975. The cedar glade flora of Bullitt County, Kentucky. Castanea40: 184–190.Google Scholar
  10. Baskin, J. M. andC. C. Baskin. 1977. An undescribed cedar glade community in middle Tennessee. Castanea42: 140–145.Google Scholar
  11. ——. 1978. Plant ecology of cedar glades in the Big Barren region of Kentucky. Rhodora80: 545–557.Google Scholar
  12. —,E. Quarterman andC. Caudle. 1968. Preliminary check-list of the herbaceous vascular plants of cedar glades. J. Tennessee Acad. Sci.43: 65–71.Google Scholar
  13. Bayer, R. J. andG. L. Stebbins. 1981. Chromosome numbers of North American species ofAntennaria Gaertner (Asteraceae: Inuleae). Amer. J. Bot.68: 1342–1349.Google Scholar
  14. Beaudry, J. R. 1963. Studies onSolidago L. VI. Additional chromosome numbers of taxa of the genusSolidago. Canad. J. Genet. Cytol.5: 150–174.Google Scholar
  15. Bellmer, Sister Elizabeth Henry. 1968. Distribution, variation, and chromosome number in the Appalachian shale barren endemicEriogonum allenii Watson. Ph.D. diss., The Catholic University of America.Google Scholar
  16. Bodkin, N. 1973. Shale barren species and endemic derivation. Madison College Studies and Research31: 80–100.Google Scholar
  17. Borgen, L. 1979. Karyology of the Canarian flora. Pages 329–346in D. Bramwell (ed.). Plants and islands. Academic Press, London.Google Scholar
  18. Bradshaw, A. D. 1971. Plant evolution in extreme environments. Pages 20–50in R. Creed (ed.). Ecological genetics and evolution. Blackwell, Oxford.Google Scholar
  19. Bramwell, D. 1972. Endemism in the flora of the Canary Islands. Pages 141–159in D. H. Valentine (ed.). Taxonomy phytogeography and evolution. Academic Press, London.Google Scholar
  20. Braun, E. L. 1950. Deciduous forests of eastern North America. Blakiston Co., Philadelphia.Google Scholar
  21. —. 1955. The phytogeography of unglaciated eastern United States and its interpretation. Bot. Rev.21: 297–375.Google Scholar
  22. Brummitt, R. K. 1965. New combinations in North AmericanCalystegia. Ann. Missouri Bot. Gard.52: 214–216.Google Scholar
  23. Cain, S. A. 1971. Foundations of plant geography. Hafner Publ. Co., New York (facsimile of 1944 edition).Google Scholar
  24. Cardona, M. A. andJ. Contandriopoulos. 1979. Endemism and evolution in the islands of the western Mediterranean. Pages 133–169in D. Bramwell (ed.). Plants and islands. Academic Press, London.Google Scholar
  25. Carlquist, S. 1981. Chance dispersal. Amer. Sci.69: 509–516.Google Scholar
  26. Chaudhri, M. N. 1968. A revision of the Paronychiinae. Drukkerij H. Gianotten N. V.Tilburg.Google Scholar
  27. Clarkson, R. B. 1966. The vascular flora of the Monongahela National Forest, West Virginia. Castanea31: 1–119.Google Scholar
  28. Cleland, R. 1958. The evolution of the North American oenotheras of the “biennis” group. Planta51: 378–398.Google Scholar
  29. —. 1964. The evolutionary history of the North American evening primroses of the “biennis group.” Proc. Amer. Philos. Soc.108: 88–98.Google Scholar
  30. Constance, L. 1963. Amphitropical relationships in the herbaceous flora of the Pacific Coast of North and South America: A symposium. Introduction and historical review. Quart. Rev. Biol.38: 109–116.Google Scholar
  31. Core, E. L. 1940a. The shale barren flora of West Virginia. Proc. West Virginia Acad. Sci.14: 27–36.Google Scholar
  32. —. 1940b. Notes on the mid-Appalachian species ofParonychia. Virginia J. Sci.1: 110–116.Google Scholar
  33. —. 1941. The North American species ofParonychia Amer. Midl. Naturalist26: 369–397.Google Scholar
  34. —. 1952. Ranges of some plants of the Appalachian shale barrens. Castanea17: 105–116.Google Scholar
  35. —. 1966. Vegetation of West Virginia. McClain Printing Co. Parsons, West Virginia.Google Scholar
  36. — andH. A. Davis. 1953. New plant records for West Virginia. Castanea18: 31.Google Scholar
  37. Craig, A. J. 1969. Vegetational history of the Shenandoah Valley, Virginia. Geol. Soc. Amer. Spec. Pap.123: 283–296.Google Scholar
  38. Critchfield, W. B. 1980. Origins of the eastern deciduous forest. Pages 1–14in P. P. Feret and T. L. Sharik (eds.). Dendrology in the eastern deciduous forest biome. Publ. No. FWS-2-80, School of Forestry and Wildlife Resources, VPI and SU, Blacksburg, Virginia.Google Scholar
  39. Cronquist, A. 1980. Vascular flora of the Southeastern United States, Vol. 1: Asteraceae. Univ. North Carolina Press, Chapel Hill.Google Scholar
  40. Cruden, R. W. 1977. Pollen-ovule ratios: A conservative indicator of breeding systems in flowering plants. Evolution31: 32–46.Google Scholar
  41. Daubenmire, R. 1978. Plant geography with special reference to North America. Academic Press, New York.Google Scholar
  42. Davis, M. B. 1976. Pleistocene biogeography of temperate deciduous forests. Geosci. Man13: 13–26.Google Scholar
  43. Deevey, E. S. 1949. Biogeography of the Pleistocene. Bull. Geol. Soc. Amer.60: 1315–1416.Google Scholar
  44. Dietrich, R. V. 1970. V = f(S…). Pages 67–99in P. C. Holt. (ed.). The distributional history of the biota of the southern Appalachians. Pt. II. Flora. Res. Div. Monogr. 2, Virginia Polytechnic Institute and State University, Blacksburg, Virginia.Google Scholar
  45. Dorf, E. 1959. Climatic changes of the past and present. Amer. Sci.13: 181–210.Google Scholar
  46. Erickson, R. O., L. G. Brenner andJ. Wraight. 1942. Dolomitic glades of east-central Missouri. Ann. Missouri Bot. Gard.29: 89–101.Google Scholar
  47. Favarger, C. andJ. Contandriopoulos. 1961. Essai sur l’endémisme. Ber. Schweiz. Bot. Ges.71: 384–408.Google Scholar
  48. Fenneman, N. M. 1938. Physiography of eastern United States. McGraw-Hill, New York.Google Scholar
  49. Fernald, M. L. 1924. Isolation and endemism in north-eastern America and their relation to the age and area hypothesis. Amer. J. Bot.11: 558–572.Google Scholar
  50. —. 1926. The antiquity and dispersal of vascular plants. Quart. Rev. Biol.1: 212–245.Google Scholar
  51. —. 1936. Plants from the Outer Coastal Plain of Virginia. Notes onParonychia, § Anychia. Rhodora38: 416–421.Google Scholar
  52. —. 1950. Gray’s manual of botany, 8th ed. American Book Company, New York.Google Scholar
  53. Flory, W. S. 1970.Phlox of the Appalachians: Distribution and relationships. Pages 193–213in P. C. Holt (ed.). The distributional history of the biota of the Southern Appalachians. Pt. II. Flora. Res. Div. Monogr. 2, Virginia Polytechnic Institute and State University, Blacksburg, Virginia.Google Scholar
  54. Fosberg, F. R. 1954. Notes on plants of the eastern United States. Castanea19: 25–37.Google Scholar
  55. Frakes, L. A. 1963. Stratigraphy of the nonred Upper Devonian across Pennsylvania. Pages 183–199in V. C. Shepps (ed.). Symposium on Middle and Upper Devonian stratigraphy of Pennsylvania and adjacent states. Pennsylvania Geol. Surv., 4th Ser., G-39.Google Scholar
  56. -. 1967. Stratigraphy of the Devonian Trimmers Rock in eastern Pennsylvania. Pennsylvania Geol. Surv., 4th Ser., Bull. G–51.Google Scholar
  57. Freer, R. S. 1935. Further notes on the flora of the Blue Ridge Mountains of Virginia. Claytonia2: 5–8.Google Scholar
  58. Gillet, J. M. andT. Mosquin. 1967.In IOPB chromosome number reports X. Taxon16: 146–157.Google Scholar
  59. Gleason, H. A. 1952. The new Britton and Brown illustrated flora of the northeastern United States and adjacent Canada. Lancaster Press, Lancaster. 3 vols.Google Scholar
  60. — andA. Cronquist. 1963. Manual of vascular plants of northeastern United States and adjacent Canada. D. Van Nostrand Company, Inc., Princeton.Google Scholar
  61. Gorman, M. 1979. Island ecology. Chapman and Hall, London.Google Scholar
  62. Graham, A. 1964. Origin and evolution of the biota of southeastern North America: Evidence from the fossil plant record. Evolution18: 571–585.Google Scholar
  63. Grant, V. 1981. Plant speciation, 2nd ed. Columbia University Press, New York.Google Scholar
  64. Greuter, W. 1972. The relict element of the flora of Crete and its evolutionary significance. Pages 161–177in D. H. Valentine (ed.). Taxonomy phytogeography and evolution. Academic Press, London.Google Scholar
  65. Grun, P. 1959. Variability of accessory chromosomes in native populations ofAllium cernuum. Amer. J. Bot.46: 218–224.Google Scholar
  66. Guthrie, R. L. 1960.In Documented chromosome numbers of plants. Madroño15: 219–221.Google Scholar
  67. —. 1968. A biosystematic study ofTaenidia andPseudotaenidia (Umbelliferae). Ph.D. diss., West Virginia University, Morgantown, West Virginia.Google Scholar
  68. Hack, J. T. 1969. The area, its geology: Cenozoic development of the southern Appalachians. Pages 1–17in P. C. Holt (ed.). The distributional history of the biota of the southern Appalachians. Pt. I. Invertebrates. Res. Div. Monogr. I, Virginia Polytechnic Institute, Blacksburg, Virginia.Google Scholar
  69. Hammond, A. L. 1976. Paleoclimate: Ice age was cool and dry. Science191: 455.PubMedGoogle Scholar
  70. Harper, J. 1977. Population biology of plants. Academic Press, London.Google Scholar
  71. Hart, R. 1980. The coexistence of weeds and restricted native plants on serpentine barrens in southeastern Pennsylvania. Ecology61: 688–701.Google Scholar
  72. Heiser, C. B., Jr. 1969. The North American sunflowers (Helianthus). Mem. Torrey Bot. Club22: 1–218.Google Scholar
  73. Henry, L. K. 1954. Shale-barren flora in Pennsylvania. Proc. Pennsylvania Acad. Sci.28: 65–68.Google Scholar
  74. Hopkins, M. 1937.Arabis in eastern and central North America. Rhodora39: 63–148; 155–186.Google Scholar
  75. Hunnewell, F. W. 1923. A new station for three local Appalachian plants. Rhodora25: 168.Google Scholar
  76. —. 1929. Some local plants of Virginia. Rhodora31: 256–257.Google Scholar
  77. Jones, A. G. 1980. Data on chromosome numbers inAster (Asteraceae), with comments on the status and relationships of certain North American species. Brittonia32: 240–261.Google Scholar
  78. Keener, C. S. 1966. Documented plant chromosome numbers 1966:1. Sida2: 434–435.Google Scholar
  79. —. 1967. A biosystematic study ofClematis subsectionIntegrifoliae (Ranunculaceae). J. Elisha Mitchell Sci. Soc.83: 1–41.Google Scholar
  80. —. 1970. The natural history of the mid-Appalachian shale barren flora. Pages 215–248in P. C. Holt (ed.). The distributional history of the biota of the southern Appalachians. Pt. II. Flora. Res. Div. Monogr. 2, Virginia Polytechnic Institute and State University, Blacksburg, Virginia.Google Scholar
  81. Kozak, S. J. 1965. Geology of the Millboro Quadrangle, Virginia. Virginia Division of Mineral Resources Rept. of Invest. 8.Google Scholar
  82. Kruckeberg, A. R. 1951. Intraspecific variability in the response of certain native plant species to serpentine soil. Amer. J. Bot.38: 408–419.Google Scholar
  83. —. 1954. The ecology of serpentine soils. III. Plant species in relation to serpentine soils. Ecology35: 267–274.Google Scholar
  84. —. 1967. Ecotypic response to ultra-mafic soils by some plant species of northwestern United States. Brittonia19: 133–151.Google Scholar
  85. —. 1969. Soil diversity and the distribution of plants with examples from western North America. Madroño20: 129–154.Google Scholar
  86. Kucera, C. L. andS. C. Martin. 1957. Vegetation and soil relationships in the glade region of the southwestern Missouri Ozarks. Ecology38: 285–291.Google Scholar
  87. Ledingham, G. F. 1960. Chromosome numbers inAstragalus andOxytropis. Canad. J. Genet. Cytol.2: 119–128.Google Scholar
  88. Lewis, H. 1966. Speciation in flowering plants. Science152: 167–172.PubMedGoogle Scholar
  89. MacArthur, R. H. andE. O. Wilson. 1967. The theory of island biogeography. Princeton University Press, Princeton, New Jersey.Google Scholar
  90. Martin, P. S. 1958. Pleistocene ecology and biogeography of North America. Pages 375–420in C. L. Hubbs (ed.). Zoogeography, AAAS Publ. 51, Washington, D.C.Google Scholar
  91. Mason, H. L. 1946a. The edaphic factor in narrow endemism. I. The nature of environmental influences. Madrono8: 209–226.Google Scholar
  92. —. 1946b. The edaphic factor in narrow endemism. II. The geographic occurrence of plants of highly restricted patterns of distribution. Madroño8: 241–257.Google Scholar
  93. McVaugh, R. 1943. The vegetation of the granitic flat-rocks of the southeastern United States. Ecol. Monogr.13: 119–166.Google Scholar
  94. Mikesell, P. B. 1975. A biosystematic study of theCalystegia spithamaea-catesbeiana complex (Convolvulaceae). Ph.D. diss., The Pennsylvania State University.Google Scholar
  95. Moral, R. del. 1982. Control of vegetation on contrasting substrates: Herb patterns on serpentine and sandstone. Amer. J. Bot.69: 227–238.Google Scholar
  96. Mosquin, T. andJ. M. Gillett. 1965. Chromosome numbers in AmericanTrifolium (Leguminosae). Brittonia17: 136–143.Google Scholar
  97. Munz, P. A. 1965. Onagraceae. N. Amer. Flora, II.5: 1–278.Google Scholar
  98. Murdy, W. H. 1968. Plant speciation associated with granite outcrop communities of the Southeastern Piedmont. Rhodora70: 394–407.Google Scholar
  99. Nelson, G. andN. Platnick. 1981. Systematics and biogeography: Cladistics and vicariance. Columbia University Press, New York.Google Scholar
  100. — andD. E. Rosen. 1981. Vicariance biogeography: A critique. Columbia University Press, New York.Google Scholar
  101. Ornduff, R., P. H. Raven, D. W. Kyhos andA. R. Kruckeberg. 1963. Chromosome numbers in Compositae. III. Senecioneae. Amer. J. Bot.50: 131–139.Google Scholar
  102. —,T. Mosquin, D. W. Kyhos andP. H. Raven. 1967. Chromosome numbers in Compositae. VI. Senecioneae. II. Amer. J. Bot.54: 205–213.Google Scholar
  103. Pijl, L.van der. 1969. Principles of dispersal in higher plants. Springer-Verlag, Berlin.Platt, R. B. 1950. Two mid-Appalachian violets. Castanea15: 126–129.Google Scholar
  104. —. 1951. An ecological study of the mid-Applachian shale barrens and the plants endemic to them. Ecol. Monogr.21: 269–300.Google Scholar
  105. Prentice, H. C. 1976. A study in endemism:Silene diclinis. Biol. Conserv.10: 15–30.Google Scholar
  106. Proctor, J. andR. J. Woodell. 1975. The ecology of serpentine soils. Advances Ecol. Res.9: 255–366.Google Scholar
  107. Räunkiaer, C. 1934. The life forms of plants and plant geography. Oxford University Press, Oxford.Google Scholar
  108. Raven, P. H., W. Dietrich andW. Stubbe. 1979. An outline of the systematics ofOenothera subsect.Euoenothera (Onagraceae). Syst. Bot.4: 242–252.Google Scholar
  109. Reveal, J. L. 1968. Notes on the Texas eriogonums (Polygonaceae). Sida3: 195–205.Google Scholar
  110. —. 1970.Eriogonum. Pages 510–516in D. S. Correll and M. C. Johnston. Manual of the vascular plants of Texas. Texas Research Foundation, Renner, Texas.Google Scholar
  111. —. 1979. Biogeography of the Intermountain Region: A speculative appraisal. Mentzelia4: 1–92.Google Scholar
  112. Richardson, I. B. K. 1978. Endemic taxa and the taxonomist. Pages 245–262in H. E. Street (ed.). Essays in plant taxonomy. Academic Press, London.Google Scholar
  113. Ridley, H. N. 1925. Endemic plants. J. Bot.63: 182–183.Google Scholar
  114. Rune, O. 1954. Notes on the flora of the Gaspé Peninsula. Svensk Bot. Tidskr.48: 117–136.Google Scholar
  115. Runemark, H. 1969. Reproductive drift, a neglected principle in reproductive biology. Bot. Not.122: 90–129.Google Scholar
  116. Russell, N. H. 1965. Violets (Viola) of central and eastern United States: An introductory survey. Sida2: 1–113.Google Scholar
  117. Silberhorn, G. M. 1968. The shale barren flora of the Virginias. The Radford Review22: 111–118.Google Scholar
  118. Simberloff, D. 1974. Equilibrium theory of island biogeography and ecology. Ann. Rev. Ecol. Syst.5: 161–182.Google Scholar
  119. Small, J. K. 1933. Manual of the southeastern flora. Publ. by the author, New York.Google Scholar
  120. Smith, F. H. 1938. Some chromosome numbers in the Cruciferae. Amer. J. Bot.25: 220–221.Google Scholar
  121. Smith, D. M. andD. Levin. 1967. Karyotypes of eastern North AmericanPhlox. Amer. J. Bot.54: 324–334.Google Scholar
  122. Stebbins, G. L., Jr. 1935. A new species ofAntennaria from the Appalachian Region. Rhodora37: 229–237.Google Scholar
  123. —. 1942. The genetic approach to problems of rare and endemic species. Madrono6: 241–258.Google Scholar
  124. —. 1950. Variation and evolution in plants. Columbia University Press, New York.Google Scholar
  125. —. 1980. Rarity of plant species: A synthetic viewpoint. Rhodora82: 77–86.Google Scholar
  126. — andJ. Major. 1965. Endemism and speciation in the California flora. Ecol. Monogr.35: 1–35.Google Scholar
  127. Steele, E. S. 1911. New or noteworthy plants from the eastern United States. Contr. U.S. Natl. Herb.13: 359–374.Google Scholar
  128. Steyermark, J. A. 1934. Some features of the flora of the Ozark Region of Missouri. Rhodora36: 214–233.Google Scholar
  129. Stinson, H. T. 1953. Cytogenetics and phylogeny ofOenothera argillicola Mackenz. Genetics38: 389–406.PubMedGoogle Scholar
  130. —. 1960. Extranuclear barriers to interspecific hybridization betweenOenothera hookeri andOenothera argillicola. Genetics45: 819–838.PubMedGoogle Scholar
  131. Street, H. E. (ed.). 1978. Essays in plant taxonomy. Academic Press, London.Google Scholar
  132. Sweeney, C. R. 1970. Monograph of the genusSilphium: I.Silphium compositum Michaux (Compositae). Ohio J. Sci.70: 226–233.Google Scholar
  133. Taylor, R. L. andR. P. Brockman. 1966. Chromosome numbers of some western Canadian plants. Canad. J. Bot.44: 1093–1103.Google Scholar
  134. Valentine, D. H. (ed.). 1972. Taxonomy, phytogeography and evolution. Academic Press, London.Google Scholar
  135. Walters, S. M. 1978. British endemics. Pages 263–274in H. E. Street (ed.). Essays in plant taxonomy. Academic Press, London.Google Scholar
  136. Watts, W. A. 1979. Late Quaternary vegetation of central Appalachia and the New Jersey Coastal Plain. Ecol. Monogr.49: 427–469.Google Scholar
  137. —. 1980. The Late Quaternary vegetation history of the southeastern United States. Ann. Rev. Ecol. Syst.11: 387–409.Google Scholar
  138. Webb, D. A. 1966. Dispersal and establishment: What do we really know? Pages 93–102in J. G. Hawkes (ed.). Reproductive biology and taxonomy of vascular plants. B.S.B.I. Conf. Reports, No. 9. Pergamon Press, Oxford.Google Scholar
  139. Wherry, E. T. 1929. Three shale-slope plants in Maryland. Torreya29: 104–107.Google Scholar
  140. —. 1930a. Plants of the Appalachian shale-barrens. J. Wash. Acad. Sci.20: 44–52.Google Scholar
  141. —. 1930b. A long lostPhlox. J. Wash. Acad. Sci.20: 25–29.Google Scholar
  142. —. 1933. Four shale-barren plants in Pennsylvania. Proc. Pennsylvania Acad. Sci.7: 161–164.Google Scholar
  143. —. 1935. Fifteen notable shale-barren plants. Claytonia2: 19–22.Google Scholar
  144. —. 1944. A classification of endemic plants. Ecology25: 247–248.Google Scholar
  145. —. 1953. Shale-barren plants on other geological formations. Castanea18: 64–65.Google Scholar
  146. —. 1954–56. Our dwarf bindweeds. Bartonia28: 32–33.Google Scholar
  147. -. 1955. The genusPhlox. Morris Arboretum Monographs HI, Philadelphia.Google Scholar
  148. —. 1964. Some Pennsylvania barrens and their flora. II. Bartonia34: 8–11.Google Scholar
  149. — andJ. E. Benedict, Jr. 1939. Plant finds in June, 1939. Castanea4: 137–138.Google Scholar
  150. Wiley, E. O. 1980. Phylogenetic systematics and vicariance biogeography. Syst. Bot.5: 194–220.Google Scholar
  151. Wiley, E. O.. 1981. Phylogenetics: The theory and practice of phylogenetic systematics. John Wiley, New York.Google Scholar
  152. Willis, J. C. 1922. Age and area: A study of geographical distribution and origin of species. Cambridge University Press, Cambridge.Google Scholar
  153. Wilson, K. A. 1960. The genera of Convolvulaceae in the southeastern United States. J. Arnold Arbor.41:298–317.Google Scholar
  154. Wood, C. E., Jr. 1944. Notes on the flora of Roanoke County, Virginia. Rhodora46: 69–86; 135–142.Google Scholar
  155. —. 1972. Morphology and phytogeography: The classical approach to the study of disjunctions. Ann. Missouri Bot. Gard.59: 107–124.Google Scholar
  156. Wright, H. E. 1972. Interglacial and postglacial climates. The pollen record. Quaternary Res.2: 274–282.Google Scholar
  157. Wyatt, R. andN. Fowler. 1977. The vascular flora and vegetation of the North Carolina granite outcrops. Bull. Torrey Bot. Club104: 245–253.Google Scholar

Copyright information

© The New York Botanical Garden 1983

Authors and Affiliations

  • Carl S. Keener
    • 1
  1. 1.202 Buckhout LaboratoryThe Pennsylvania State UniversityUniversity Park

Personalised recommendations