- PNIE v.17 item : Atkinson, George F. Development and biology of Armillaria / George F. Atkinson.
p. [229]-229 ; 22 cm. "Reprinted from the Botanical Gazette, 49: No. 3 March, 1910."
- PNIE v.17 item : Atkinson, George F. Note on the Genus Harpochytrium / George F. Atkinson.
p. [3]-8 : ill. ; 22 cm. "Reprinted from the Journal of Mycology, 10:3-8. Jan., 1904."
- PNIE v.17 item : Atkinson, George F. Notes for students / George F. Atkinson
p. [76]-79 : ill. ; 22 cm. "Botanical Gazette, volume 47, January, 1909."
- PNIE v.17 item : Atkinson, George F. Observations on Polyporus Lucidus Leys. and some of its allies from Europe and North America / George F. Atkinson.
p. [321]-338 : ill. ; 22 cm. "Botanical Gazette, volume 56, number 5, November, 1908."
- PNIE v.17 item : Atkinson, George F. Preliminary notes on some new species of Agaricaceae and Clavaria / by George F. Atkinson.
p. [365]-376 ; 22 cm. "Reprinted from the Annales Mycologici, Vol. VII, No. 4, 1909."
- PNIE v.17 item : Atkinson, George F. President's Address to the Alpha Chapter of the Sigma XI / George F. Atkinson.
10 p. : ill. ; 22 cm.
- PNIE v.17 item : Atkinson, George F. Protocoronospora, a new genus of fungi / George F. Atkinson and C.W. Edgerton.
p. [185]-186 ; 22 cm. "Reprinted from the Journal of Mycology, 13:185-186, September 1907."
- PNIE v.17 item : Atkinson, George F. Some fungus parasites of algae / George F. Atkinson.
p. [321]-338 : ill. ; 22 cm. "Botanical Gazette, volume 58, number 5, November, 1909."
- PNIE v.17 item : Atkinson, George F. The Genera Balansia and Dothichloe in the United States with a consideration of their economic importance / by George F. Atkinson.
p. [248]-267 : ill. ; 22 cm. "Reprinted from the Journal of Mycology, 11:248-267, November 1905."
- PNIE v.17 item : Atkinson, George F. The influence of mushrooms on the growth of some plants / by George F. Atkinson.
p. [217]-234 : ill. ; 22 cm. "Bulletin 240, June, 1906."
- PNIE v.17 item : Atkinson, George F. The origin and taxonomic value of the "veil" in Dictyophora and Ithyphallus / George F. Atkinson.
20 p. : ill. ; 22 cm. "Botanical Gazette, volume LI, number 1, January, 1911."
- PNIE v.17 item : Atkinson, George F. The preparation of material for general class use / George F. Atkinson.
p. [372]-376 ; 22 cm. "Botanical Gazette, May, 1897."
- PNIE v.17 item : Atkinson, George F. Two new species belonging to Naucoria and Stropharia / George F. Atkinson.
p. [193]-194 : ill. ; 22 cm. "Reprinted from the Journal of Mycology, 12: 193-4, Sept., 1906."
- PNIE v.17 item : Atkinson, George Francis, 1854-1918. Damping off / by Geo. F. Atkinson.
p. 234-272 : ill. ; 22 cm.
- PNIE v.17 item : Atkinson, George Francis, 1854-1918. Mushroom growing for amateurs / by Geo. F. Atkinson and Robert Shore.
p. 416-424 : ill. ; 22 cm. "Cornell University, Agricultural Experiment Station of the College of Agriculture, Department of Botany, March, 1905, Bulletin 227."
- PNIE v.17 item : Barnhart, John Hendley, 1871-1949. Family nomenclature.
24 p. : ill. ; 22 cm. Cover title. "Reprinted from the Bulletin of the Torrey Botanical Club, vol. XXII, no. 1, Jan. 1895."
- PNIE v.17 item : Bartlett, Harley Harris, 1886-1960. The source of the drug dioscorea : with a consideration of the Dioscoreae found in the United States / by Harley Harris Bartlett.
29 p. : ill. ; 22 cm. "Bureau of Plant Industry-Bulletin, no. 189, 1910."
- PNIE v.17 item : Borge, O. Die susswasseralgenflora spitzbergens / von O. Borge.
39 p. ; 22 cm. "Videnskapsselskapets Skrifter, I. Mat.-naturv. Klasse 1911, no. 11."
- PNIE v.17 item : Clute, Willard Nelson, 1869- . An Outdoor Laboratory / By Willard N. Clute.
p. [402]-405 ; 22 cm. "School Science and Mathematics."
- PNIE v.17 item : Contribution towards a monograph of the Laboulbeniaceae.
2 p. : ill. ; 22 cm. "Reprinted from Science, N. S., vol. VII, no. 178, pages 752-753, May 27, 1898."
- PNIE v.17 item : Cordley, A. B. Some observations on apple tree Anthracnose / A.B. Cordley.
p. [48]-58 : ill. ; 22 cm. "Botanical Gazette, July, 1900."
- PNIE v.17 item : Curtis, M. A. (Moses Ashley), 1808-1872. Geological and natural history survey of North Carolina, part III, botany : containing a catalogue of the plants of the state / by M.A. Curtis.
157 p. : ill. ; 22 cm.
- PNIE v.17 item : Diseases of plants induced by cryptogamic parasites.
7 p. ; 22 cm. "Reprinted from Science, N. S., vol. V., no. 122, pages 696-699, April 30, 1897."
- PNIE v.17 item : Edgerton, C. W. (Claude Wilbur), 1880- . Notes on a parasitic Gnomonia / Claude Wilbur Edgerton.
p. [593]-597 : ill. ; 22 cm. "From the Bulletin of the Torrey Botanical Club, 34: 593-597. 1908."
- PNIE v.17 item : Edgerton, C. W. (Claude Wilbur), 1880- . The physiology and development of some Anthracnoses / by Claude Wilbur Edgerton.
p. [367]-408 : ill. ; 22 cm. "Botanical Gazette, vol. 45: 367-408, June 1908."
- PNIE v.17 item : Hirsh, Pauline E. The development of air chambers in the Ricciaceae / Pauline E. Hirsh.
p. [73]-77 : ill. ; 22 cm. "From the Bulletin of the Torrey Botanical Club, 37: 73-77. 1910."
- PNIE v.17 item : Maxon, William R. A list of the ferns and fern allies of North America north of Mexico : with principal synonyms and distribution / by William R. Maxon.
p. [619]-651 ; 22 cm. "From the Proceedings of the United States National Museum, Vol. XXIII, pages 619-651, no. 1226."
- PNIE v.17 item : Ramaley, Francis. Remarks on some northern Colorado plant communities with special reference to Boulder Park / by Francis Ramaley.
p. [223]-236 : ill. ; 22 cm. "Reprinted from University of Colorado Studies, Vol. VII, No. 4, Boulder, Colo., June, 1910."
- PNIE v.17 item : Schaffner, John H. The classification of plants, VI / John H. Schaffner.
p. [289]-260 : ill. ; 22 cm. "Reprinted from The Ohio Naturalist, vol. XI, no. 5, March, 1911."
- PNIE v.17 item : Schaffner, John H. The gymnosperms of Ohio / John H. Schaffner.
p. [9]-12 ; 22 cm. "The Ohio Naturalist, vol. X, no. 1, November, 1909."
- PNIE v.17 item : Spalding, Volney Morgan, 1849- . Present problems in plant ecology: problems of local distribution in arid regions.
p. [453]-463 : ill. ; 22 cm. "From the Smithsonian Report for 1909, Pages 453-463."
- PNIE v.17 item : Squier, George Owen, 1865- . On the absorption of electromagnetic waves by living vegetable organisms / George O. Squier.
32 p. : ill. ; 22 cm. Cover title. "Reprinted from Major General MacArthur's Report to the War Department on the military maneuvers in the Pacific Division, 1904." - Includes bibliographical references.
- PNIE v.17 item : Timm, R. Die Ausstreuung der Moossporen und die ZweckmaTHigkeit im Naturgeschehen / von R. Timm.
p. [84]-136 : ill. ; 22 cm. "Sonder-Abdruck aus den Verhandlungen des Naturw. Vereins in Hamburg 1909, 3. Folge XVII."
- PNIE v.17 item : Topics for examination-mycology.
11 p. ; 22 cm.
- PNIE v.17 item : Wille, N. Algologische Notizen VII-VIII / von N. Wille.
24 p. ; 22 cm. "Separataftryk af "Nyt Magazin f. Naturvidenskab." B. 39, H. 1. Krania 1901."
- PNIE v.17 item : Wille, N. Mikal Heggelund Foslie / Af N. Wille.
p. [353]-356 ; 22 cm. "Saetryk af'Naturen's decemberhefte 1909."
- PNIE v.18 item : Canby, Wm. M. A new silphium / Wm. M. Canby.
p. [139]-140 ; 22 cm. "Botanical Gazette, February 1899."
- PNIE v.18 item : Coulter, John M. Contribution to the life-history of Ranunculus / John M. Coulter.
p. [73]-88 : ill. ; 22 cm. "Botanical Gazette, volume XXV, number 2, February 1898."
- PNIE v.18 item : Cowles, Henry Chandler - The ecological relations of the vegetation on the sand dunes of Lake Michigan : geographical relations of the dune floras / Henry Chandler Cowles.
p. [95]-117 : ill. ; 22 cm. "Botanical Gazette, February 1899."
- PNIE v.18 item : Duggar, B. M. Notes on the maximum thermal death-point of Sporotrichum Globuliferum / B.M. Duggar.
p. [131]-136 : ill. ; 22 cm. "Botanical Gazette, February 1899."
- PNIE v.18 item : Eriksson, Jakob. A general review of the principal results of Swedish research into grain rust / Jakob Eriksson.
p. [26]-38 ; 22 cm. "Botanical Gazette, January 1898."
- PNIE v.18 item : Ganong, W. F. Society for plant morphology and physiology / W.F. Ganong.
p. [106]-118 ; 22 cm. "Botanical Gazette, February 1898."
- PNIE v.18 item : Golden, Katherie E. Red yeasts / Katherine E. Golden and Carleton G. Ferris.
p. [39]-46 : b ill. ; 22 cm. "Botanical Gazette, January 1898."
- PNIE v.18 item : Johnson, Duncan S. On the leaf and sporocarp of Pilularia / Duncan S. Johnson.
16 p. ; 22 cm. "Botanical Gazette, volume XXVI, number 1, July 1898."
- PNIE v.18 item : Noll, F. Julius Von Sachs : a biographical sketch with portrait / F. Noll.
p. 12 : ill. ; 22 cm. "Botanical Gazette, vol. XXV, no. 1, January 1898."
- PNIE v.18 item : Pollard, Charles Louis - Further observations on the eastern acaulescent violets / Charles Louis Pollard.
p. [325]-348 : ill. ; 22 cm. "Botanical Gazette, November 1898."
- PNIE v.18 item : Rowlee, W. W. Descriptions of two willows from Central Mexico / W.W. Rowlee.
p. [136]-138 : ill. ; 22 cm. "Botanical Gazette, February 1899."
- PNIE v.18 item : Sargent, Charles Sprague, 1841-1927. New or little known North American trees / Charles S. Sargent.
81-94 p. ; 22 cm. Title from cover-page. "Reprinted from the Botanical gazette, vol. XXVII, no.2, February 1899"
- PNIE v.18 item : Stevens, F. L. A peculiar case of spore distribution / F.L. Stevens.
p. [138]-139 : ill. ; 22 cm. "Botanical Gazette, February 1899."
- PNIE v.18 item : Stevens, F. L. The effect of aqueous solutions upon the germination of fungus spores / F.L. Stevens.
377-406 p. : ill. ; 22 cm. "Botanical Gazette, volume 26, number 6, December 1898."
- PNIE v.18 item : The society for plant morphology and physiology : Columbia meeting.
p. [118]-152 ; 22 cm. "Botanical Gazette, February 1899."
- PNIE v.18 item : The tree opuntias of the United States.
p. [119]-144 : ill. ; 22 cm. "Botanical Gazette, February 1898."
- PNIE v.19 item : Chamberlain, Charles J. Fertilization and embryogeny in Dioon Edule / Charles J. Chamberlain.
p. [415]-429 : ill. ; 22 cm. "Botanical Gazette, vol. 50, December 1910."
- PNIE v.19 item : Chamberlain, Charles J. Nuclear phenomena of sexual reproduction in gymnosperms / Charles J. Chamberlain.
p. [595]-603 ; 22 cm. "Reprinted from The American Naturalist, vol. XLIV., October, 1910."
- PNIE v.19 item : Chamberlain, Charles J. The adult cycad trunk / Charles J. Chamberlain.
p. [81]-104 : ill. ; 22 cm. "Botanical Gazette, volume LII, number 2, August 1911."
- PNIE v.19 item : Dorfleria.
1 v. : ill. (incl. ports.) ; 27 cm. "Internationale Zeitschrift fur Forderung praktischer Intertanik, Bibliographie der nicht selbstandig erscheinenden botanischen Arbeiten und botanisches Offertenblatt." - Title from cover.
- PNIE v.19 item : Fitzpatrick, T. J. A bibliography of Iowa State Publications for 1904 and 1905 / by T.J. Fitzpatrick.
p. [337]-408 ; 22 cm. "Iowa Journal of History and Politics, 1907."
- PNIE v.19 item : Lloyd, C. G. (Curtis Gates), 1859-1926. Mycological notes.
No. 30 (Feb. 1908) : ill. ; 23-29 cm.
- PNIE v.19 item : Salisbury, Richard Anthony - On the cultivation of rare plants ; especially such as have been introduced since the death of Mr. Philip Miller / by Richard Anthony Salisbury.
p. [261]-366 ; 22 cm.
- PNIE v.19 item : Trelease, William, 1857-1945. Illustrations of a "strangling" fig tree / William Trelease.
p. [161]-165, 7 p. of plates : ill. ; 22 cm. "Missouri Botanical Garden, Volume 16."
- PNIE v.19 item : Trelease, William, 1857-1945. Species in Agave / William Trelease.
p. [232]-237 : ill. ; 22 cm. "Read April 22, 1910."
- PNIE v.19 item : Trelease, William, 1857-1945. The smallest of the century plants / William Trelease.
p. [5]-15 : ill. ; 22 cm. "Reprinted from The Popular Science Monthly, January, 1911."
- PNIE v.20 item : Bergen, Joseph Y. (Joseph Young), 1851-1917. Some littoral spermatophytes of the Naples Region / J.Y. Bergen.
p. [327]-333 ; 22 cm. "Reprinted from The Botanical Gazette, 41:327-333, May, 1906."
- PNIE v.20 item : Bergen, Joseph Y. (Joseph Young), 1851-1917. Tolerance of drought by neapolitan cliff flora / J. Y. Bergen.
p. [449]-455 : ill. ; 22 cm. "Botanical Gazette, December 1905."
- PNIE v.20 item : Borge, O. Susswasser-Chlorophyceen von Feuerland und Isla Desolacion / von O. Borge.
p. [21]-34 : ill. ; 22 cm.
- PNIE v.20 item : Chamberlain, Charles J. Dioon Spinulosum / Charles J. Chamberlain.
p. [401]-413 : ill. ; 22 cm. "Reprinted from the Botanical Gazette 48: 401-413, no. 6, December 1909."
- PNIE v.20 item : Chamberlain, Charles J. Spermatogenesis in Dioon Edule / Charles J. Chamberlain.
p. [215]-236 : ill. ; 22 cm. "Reprinted from The Botanical Gazette 47:215-236, March 1909."
- PNIE v.20 item : Dall, William Healey, 1845-1927. Linnaeus as a zoologist / William H. Dall.
p. [272]-274 ; 22 cm. "Proceedings of the Washington Academy of Sciences, vol. IX, July 31, 1907."
- PNIE v.20 item : Dorety, Helen Angela. The extrafascicular cambium of Ceratozamia / Helen A. Dorety.
p. [150]-152 : ill. ; 22 cm. "Reprinted from The Botanical Gazette 47:149-152, February 1909."
- PNIE v.20 item : Dorety, Helen Angela. Vascular anatomy of the seedling of Microcycas Calocoma / Helen Angela Dorety.
p. [139]-147 : ill. ; 22 cm. "Reprinted from The Botanical Gazette 47:139-147, February 1909."
- PNIE v.20 item : Greene, Edward Lee, 1843-1915. Linnaean Memorial Address / by Edward L. Greene.
p. [241]-271 ; 22 cm. "Proceedings of the Washington Academy of Sciences, vol. IX, July 31, 1907."
- PNIE v.20 item : Lloyd, John Uri, 1849-1936. Hydrastis canadensis / By J. U. and C. G. Lloyd.
p. [75]-184 : ill. ; 22 cm. "Bulletin of the Lloyd library of botany, pharmacy and materia medica, Bulletin No. 10, Reproduction series, no. 6" - "Pharmaceutical and medical references to Hydrastis": p. 181-183. "Botanical references to Hydrastis canadensis Linnaeus": p. 183-184. Facsimile, reprint and illustrations of the article in Drugs and medicines of North America. 1884.
- PNIE v.20 item : Mottier, David M. On the prophases of the heterotypic mitosis in the embryo-sac mother-cell of lilium / by David M. Mottier.
p. [345]-352 : ill. ; 22 cm. "Annals of Botany, vol. XXIII, no. XCI, July, 1909."
- PNIE v.20 item : Ramaley, Francis. Studies in lake and streamside vegetation : Redrock Lake near Ward, Colorado / Francis Ramaley and W.W. Robbins.
p. [135]-168 : ill. ; 22 cm. "Reprinted from University of Colorado Studies, vol. VI, no. 2, Boulder, Colo., February, 1909."
- PNIE v.20 item : Underwood, Lucien Marcus, 1853-1907. Hepaticae, by Lucien Marcus Underwood.
7 p. : ill. ; 22 cm. "Systematic botany of North America. Vol. IX, Pt. 1"
- PNIE v.20 item : West, G. S. (George Stephen), 1876-1919. Report on the freshwater Algae, including Phytoplankton, of the third Tanganyika expedition ; conducted by Dr. W. A. Cunnington, 1904-1905. / By G. S. West.
p. [81]-197 : ill. ; 22 cm. Issued as Journal of the Linnean Society, v.38, no.264.
- PNIE v.20 item : Yamanouchi, Shigeo. Spermatogenesis, oogenesis, and fertilization in Nephrodium / Shigeo Yamanouchi.
p. [145]-175 : ill. ; 22 cm. "Reprinted from the Botanical Gazette 45:145-175, March 1908."
- PNIE v.20 item : Yamanouchi, Shigeo. Sporogenesis in Nephrodium / Shigeo Yamanouchi.
28 p. : ill. ; 22 cm. "Reprinted from the Botanical Gazette 45: 1-30, January 1908."
- PNIE v.21 item : Boewig, Harriet. The histology and development of Cassytha Filiformis, L. / Harriet Boewig.
p. [399]-416 : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania, vol. I, no. 3, 1904."
- PNIE v.21 item : Bunting, Martha. The structure of the cork tissues in roots of some Rosaceous Genera / Martha Bunting.
p. [54]-65 ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Session 1897-98. Volume I. Number 1. 1898."
- PNIE v.21 item : Conard, Henry S. Fasciation in the sweet potato / Henry S. Conard.
p. [205]-215 ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Session 1899-1900. Vol. I. No. 2. 1901."
- PNIE v.21 item : Conard, Henry S. Phyllody in Nelumdo / Henry S. Conard.
p. [350]-351 : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Vol. I. No. 3. 1904."
- PNIE v.21 item : Cooke, Ethel. Observations on the structure and development of Epiphegus Virginiana / Ethel Cooke and Adeline F. Schively.
p. [352]-398 : ill. ; 22 cm.
- PNIE v.21 item : Farr, Edith M. Notes on some interesting British Columbian plants / Edith M. Farr.
p. [417]-425 : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania, vol. I, no. 3, 1904."
- PNIE v.21 item : Gardner, Blanche. Studies on growth and cell division in the root of Vicia Faba... By Blanche Gardner...
p. [150]-182 : ill. ; 22 cm. Caption title. Transactions and Proceedings of the Botanical Society of Pennsylvania, Session 1899-1900. Vol. I. 1901 no. 2.
- PNIE v.21 item : Harshberger, John W. (John William), 1869-1929. A study of the fertile hybrids produced by crossing Teosinte and Maize / John W. Harshberger.
p. [231]-235 ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania, Session 1899-1900, vol. I, no. 2, 1901."
- PNIE v.21 item : Harshberger, John W. (John William), 1869-1929. Statistical information concerning the production of fruits and seeds in certain plants / John W. Harshberger.
p. [100]-109 ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Session 1897-98. Vol. I. No. 1. 1898."
- PNIE v.21 item : Harshberger, John W. (John William), 1869-1929. The relation of ice storms to trees / John W. Harshberger.
p. [345]-349 : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Sessions of 1901-1903. Vol. I. No. 3. 1904."
- PNIE v.21 item : Harshberger, John W. (John William), 1869-1929. Water storage and conduction in Senecio praecox, D.C., from Mexico / John W. Harshberger.
p. [31]-40 ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania, Session 1897-98, vol. I, Number 1, 1898."
- PNIE v.21 item : Macfarlane, J. M. Statement regarding publications from the University Botanical Department / by J.M. Macfarlane.
p. 435-436 ; 22 cm. "Transactions and proceedings of the Botanical Society of Pennsyvania sessions of 1901-1903."
- PNIE v.21 item : Macfarlane, J. M. The history, structure and distribution of Sarracenia Catesbaei, ELL / J.M. Macfarlane.
p. [426]-434 : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania, vol. I, no. 3, 1904."
- PNIE v.21 item : Macfarlane, J.M. The beach plum, viewed from botanical and economic aspects / J. M. Macfarlane.
p. [216]-230 ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania, Session 1899-1900, vol. I, no. 2, 1901."
- PNIE v.21 item : Macfarlane, John Muirhead, 1855-1943. Current problems in plant cytology. By J. M. Macfarlane ...
p. [183]-204 : ill. ; 22 cm. Caption title. Transactions and Proceedings of the Botanical Society of Pennsylvania, Session 1899-1900. Vol. I. 1901 no. 2.
- PNIE v.21 item : Macfarlane, John Muirhead, 1855-1943. Observations on some hybrids between Drosera filiformis and D. intermedia. By J. Muirhead Macfarlane ...
p. [87]-99 : ill. ; 22 cm. Caption title.
- PNIE v.21 item : McKenney, Randolph Evans Bender. Observations on the development of some embryo-sacs ... By R. E. B. McKenney ...
p. [80]-86 : ill. ; 22 cm. Caption title.
- PNIE v.21 item : Phillips, Orville P. A comparative study of the cytology and movements of the Cyanophyceae / Orville P. Phillips.
p. [237]-335 : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Sessions of 1901-1903. Vol. I. No. 3. 1904."
- PNIE v.21 item : Proceedings of the Botanical Society of Pennsylvania for Session 1897-98.
p. [111]-123 : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Session 1897-98. Vol. I. No. 1. 1898."
- PNIE v.21 item : Proceedings of the Botanical Society of Pennsylvania for Session 1899-1900.
p. [xv]-xli : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Session 1899-1900. Vol. I. No. 2. 1901."
- PNIE v.21 item : Proceedings of the Botanical Society of Pennsylvania for Sessions 1901-1903.
p. [xxxvii]-lxxxiv, [11] leaves of plates : ill. ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania. Vol. I. No. 3. 1904."
- PNIE v.21 item : Schively, Adeline Frances. Recent observations on Amphicarpaea Monoica / Adeline Frances Schively.
p. [20]-30 ; 22 cm. "Transactions and Proceedings of the Botanical Society of Pennsylvania, Session 1897-98, vol. I, no. 1, 1898."