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A Brief History of Some Major Contributors
to the Development of Palynology in the
UnitedStates
Introduction
Although the initiation of any science is extrermely difficult to pin down, most palynologists
today tend to recognize the 1916 publication on pollen ana1ysis of peat by the Swedish
geologist, Lennart von Post, as the starting point of the scientific field that is now termed
palyno1ogy. Nevertheless, the first published observations of pollen morphology by the
co-founders of plant anatomy, Nehemiah Grew and Marcello Malpighi, appeared between 1682
and 1687. Naturally, these observations would not have been possible prior to the improvement
of the compound microscope by Robert Hooke in 1665 (Wodehouse, 1935). Some of the other
early app1ications of palynology, e.g., pollen causes of allergies and pollen in honey, are
discussed in the article by Manten (1967).
Despite the fact that numerous applications of palynology have evolved, early work in the United
States commenced about 75 years ago and can be categorized as follows:
- Morphology of pollen and spores, particularly as an aid to systematic botany;
- Quaternary pollen analysis and paleoecology; and
- Paleopalynology of pre-Quaternary sediments that is often related to stratigraphy.
In the present account I will attempt to characterize quite briefly some of the most prominent
American scientists who did pioneering work in these three areas of palynology. At the
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outset I realize that this approach is foolhardy for at least two reasons: some palynologists will be
offended because their names have been omitted and, of those persons listed, some will have
worked in several areas of palynology, other than the
one where they have been placed in this account.
Pollen and Spore Morphology
Available evidence seems to indicate that Harvard University was an early center for the
investigation of pollen and spore morphology mainly due to the presence there of Irving W.
Bailey from 1909 until his death in 1967. Although Bailey was basically a plant anatomist, he
often collaborated with systematic botanists in the investigation of angiosperm genera and
families, In this connection, he firmly believed that evidence of relationships should be based on
the microscopic characteristics of all parts of the plants under investigation. One particular
approach that he found to be of value was the comparative study of pollen grains. Even though I
have not worked on that aspect of palynology for some time, I got my start in 1946 by
comparative studies of the pollen of the primitive families Magnoliaceae and Annonaceae
(Canright, 1953, 1962). Elso S. Barghoorn obtained his Ph.D. in 1941 under Bailey's guidance.
After teaching for five years at Amherst College (and starting at the magnificent annual salary of
$2,000), he joined the Harvard faculty to teach paleobotany. He is probably best known for his
description of the Precambrian microorganisms from the Gunflint Chert of Ontario. One of his
former students, J. William Schopf, has become a leader in the investigations of Precambrian
bacteria, algae and fungi from many parts of the world. He currently directs an institute for the
study of Precambrian biotas while teaching at UCLA.
Another of Barghoorn's former students who has gained prominence is Alfred Traverse (Ph. D.
Harvard, 1951). His description of the pollen from the Tertiary Brandon Lignite of Vermont
(1955) is believed to be the first paleopalynological Ph.D. dissertation in the United States. After a
5-year stint at the Bureau of Mines Lignite Laboratory in the wilds of North Dakota, he was
pleased to get an appointment at the Shell Development Company in Houston. Since 1966 he has
been a professor of Geology and Botany at the Pennsylvania State University, where he has
"turned out" a significant number of graduate students. Traverse was the President of the
International Commission for Palynology (ICP) from 1977- 1980; concurrently, I founded and
edited the ICP Newsletter. At present Traverse is the Archivist of the International Federation of
Palynological Societies (IFPS), the umbrella group that succeeded the ICP in 1984 (Canright,
1984). He was one of the authors, including G.O.W. Kremp, of the well known "Catalogue of
Fossil Spores and Pollen," which was initiated in 1957 and now includes about 43 volumes. His
recent textbook entitled "Paleopalynology" (1988) is one of a kind.
Roger P. Wodehouse was born in Toronto in 1889. After obtaining his bachelor's degree at the
University of Toronto in 1913, he attended Harvard and earned the A.M. in 1916. After
becoming naturalized, he worked as a research chemist and hay fever specia1ist in several
pharmaceutical houses in Boston and New York. He completed the Ph.D. in 1928 at Columbia
University, then joined the Leder1e Laboratories as Director of Research. His book "Pollen
Grains" first appeared in 1935 and was reprinted in 1959. In this book pollen grains are
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beautifully illustrated by detailed line drawings. One of these is the chenopod, Salsola, which is
currently featured in the logo developed for the IXth IPC that will be held in Houston, Texas next
June (Nichols, 1994).
A. Orville Dahl earned all his degrees at the University of Minnesota between 1932 and 1938.
For the next six years he taught at Harvard University. His precise research on pollen
morphology and cytology that was begun under Bailey's influence, was continued when he
returned to the Minnesota faculty in 1944. He subsequently became Chairman of the Botany
Department there; one of his former students is John Rowley (now in Sweden), who has
published extensively on exine cytology and ultrastructure.
Lucy M. Cranwell (July, 1991 Photo by J. E. Canright
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Lucy M. Cranwell (Mrs. Watson Smith) was the Head of the Botany Department in the
Auckland Museum from 1929 to 1944. She was discovered there by Watson Smith, a young
archeologist, who was on leave from his duties as an officer in the U. S. Air Force. At the close
of World War II they moved to Cambridge (MA), where Watson became a Research Associate in
Harvard's Peabody Museum Lucy continued the pollen studies she had begun in New Zealand
as a Research Associate in Botany from 1944-1950. Her study of the pollen of monocots of
New Zealand was published by the Harvard University Press in 1953, and her "Ancient Pacific
Floras - The Pollen Story" (1964) is much quoted.
The Watson Smiths moved to Tucson, Arizona in 1951, where Wat was associated with the
Arizona State Museum and Lucy became an Honorary Research Associate in Palynology in the
University of Arizona's Geochronology Laboratory. When I talked to her recently (shortly after
her 88th birthday), I learned that she is still very interested in the past and present distribution of
the southern beech, Nothofagus. She was elected an Honorary Member of AASP in 1989.
Quaternary Pollen Analysis
Between the years 1920 and 1940, a number of Americans published their observations on the
spore and pollen types recovered from bogs and lakes. The resulting analyses led to deductions
concerning the vegetation, paleoecology and paleoclimatology of the sites at the times of
deposition.
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One of the first Americans to follow the research example of Lennart von Post was John E.
Potzger. He earned his first two degrees at Butler University in Indianapolis, then obtained the
Ph.D. in Botany at Indiana University in 1932. He then returned to Butler University, where he
spent his entire professional career as an ardent plant ecologist and pollen analyst. When I taught
at Indiana University in the 50s, it used to be said (in jest?) that Potzger and his many students
had cored every bog in Indiana and surrounding states.
An outstanding scientist in this field was Paul B. Sears. He gained the A.B. degree at Ohio
Wesleyan University in 1913, then took another bachelor's degree and a master's at the
University of Nebraska, before earning his Ph.D. in botany at the University of Chicago in 1922.
After teaching botany at the University of Nebraska from 1919 to 1927, he moved to the
University of Oklahoma until 1938. For the next 12 years he served as the Head of the Botany
Department at Oberlin College in Ohio. Next, he was selected to direct the School of
Conservation at Yale University; he wore a second hat as Head of the Department of Plant
Science until his retirement in 1960 at age 69.
His many palynological research publications and, especially, his popular books on conservation
were so well regarded that he was given honorary doctoral degrees at six different universities.
Traverse and Sullivan (1983) have previously described how Sears brought Quaternary pollen
workers together by means of regular Pollen Conferences, as well as the publication of the
"Pollen and Spore Circular" between 1943 and 1954.
Closely associated with Sears at Yale was Edward S. Deevey, Jr., who joined the faculty there as
a limnologist in 1946. Previously he had earned the A.B. (1934) and the Ph.D. (1938) at Yale,
then was a Research Associate at the Woods Hole Oceanographic Institute on Cape Cod.
Herbert E. Wright, Jr., received three degrees in geology at Harvard University between 1939
and 1943. After short stints at Brown University and the U. S. Geological Survey, he joined the
faculty of the University of Minnesota in 1947. Later (1963) he was appointed as the Director of
the Limnology Research Center at the University of Minnesota. Together with David Frey, he
edited the very comprehensive volume (922 pages), "The Quaternary of the United States" in
1965. This was a review volume for the VIIth Congress of the International Association for
Quaternary Research.
David G. Frey earned all his degrees in zoology at the University of Wisconsin between 1936
and 1940. The next 5 years he was emp1oyed as an Aquatic Biologist with the U. S. Fish and
Wildlife Service in Washington, D. C. After serving on the faculty of the University of North
Carolina, he joined the Zoology Department at Indiana University in 1950 to finish out his
career. He has published extensive1y on the lirnnology and rnicropaleontology of freshwater
lakes.
Calvin J. Heusser earned his A. B. and A. M. at Rutgers University (1947-49), then obtained the
Ph.D. at Oregon State University in 1952. After a postdoctoral appointment at Yale, he became a
Research Associate of the American Geographical Society. This position led to his studies of
palynornorphs in Chilean bogs, as well as his handsome book, "The Pollen and
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Spores of Chile" (1971). His principal work, "Late Pleistocene Environments of North Pacific
North America" (1960), became a standard for Pleistocene research in the Northwest. He joined
the faculty of New York University, then the Lamont Laboratory unti1 his recent retirement.
Stanley A. Cain completed his undergraduate education at Butler University in 1924, then earned
his master's and doctoral degree by 1930 at the University of Chicago. Between 1933 and 1946
he taught at the University of Tennessee, then spent the next four years as a Research Scientist at
the Cranbrook Institute of Science. In 1950 he was appointed Head of the Department of
Conservation at the University of Michigan, where he completed his professional career.
One of Cain's graduate students was Paul S. Martin, who carne to Michigan in 1951 after
completing his undergraduate education at Cornell University. After Martin completed his
Ph.D. at Michigan in 1956, he held a postdoctora1 appointment at Yale University with Sears
and Deevey. The following year he became a Research Associate in the Geochronology
Laboratory of the University of Arizona in Tucson. After he carried out extensive field work in
the Southwest, the University of Arizona Press published his "The Last 10,000 Years--A Fossil
Pollen Record of the American Southwest" (1963). Martin has trained many students at the University of Arizona; some have gone on to
work in the relatively new field of archeological pollen analysis.
Paleopalynology
Whenever the early history of paleopalynology in North America is mentioned today, the name
of Leonard R. Wilson invariably crops up. He earned all his degrees in botany at the University
of Wisconsin between 1930 and 1936. His next ten years were spent teaching both botany and
geology at tiny Coe College in Iowa. From 1946 till 1956 he served as Head of the Geo1ogy
Department at the University of Massachusetts. After a single year at New York University, he
joined the faculty at the University of Oklahoma, with a joint appointment in the Oklahoma
Geo1ogical Survey. Because of his extensive publications on stratigraphic palynology, his
services as a consultant to oil companies were eagerly sought. During the '50's and '60's, when
American oil companies first started to recognize the va1ue of palynology to stratigraphy
(Hopping, 1967), many of Wilson's students were hired directly out of college. Wilson still
regularly goes into his office in the Oklahoma Museum of Natural History in Norman, OK and
he is now 86 years young!
Two well known palynologists who were influenced by Wi1son when they were undergraduates
at Coe College are Aureal T. Cross and Robert M. Kosanke. Cross earned the A.M. and Ph.D. at
the University of Cincinnati (1941-43) in paleobotany under J. H. Hoskins. After six years on the
faculties of the University of Cincinnati and Notre Dame, Cross accepted an
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appointment as Professor of Geology at the University of West Virginia, plus a joint appointment
with the West Virginia Geological Survey. Here he did extensive research on the correlation of
coal seams with spores of Pennsylvanian age. In 1957 he was appointed as Supervisor of the
Research Center of the Pan American Petroleum Company (=AMOCO), where he trained many
young palynologists in the various aspects of petroleum research and stratigraphic correlation.
Since 1961 he has been a Professor of both Botany and Geology at Michigan State University. In
1962 he organized a symposium for the Society of Economic Paleontologists and Mineralogists
(SEPM) at their San Francisco meeting entitled "Palynologv and Oil Exploration." Sixteen
speakers contributed to this symposium and Cross edited the resulting volume (1964). Although
now officially retired from his position at MSU, lie is still active in research at age 79.
Robert M. Kosanke joined his friend Cross in earning his master's degree at the University of
Cincinnati. However, in 1943 he took a position as Coa1 Geologist in the Illinois Geological
Survey, which turned out to be a 20-year stint. During this time, he took graduate courses at the
University of Illinois, which led to his attaining the Ph.D. in paleobotany under Wilson Stewart
in 1952. While with this Survey, he gained the reputation for doing careful, thorough research on
spores of Pennsylvanian age in the Illinois Coal Basin. This 1ed to his appointment in 1963 in
the Paleontology and Stratigraphy Branch of the U. S. Geological Survey in Denver. Until the
recent demise of the P&S Branch, he maintained his office there.
James Morton Schopf obtained the B.A. at the University of Wyoming in 1930 at the tender age
of 19. He then attended the University of Illinois where he gained his master's degree two years
later. He served as paleobotanist and coa1 geologist with the Illinois Geo1ogical Survey in
Urbana from 1934 to 1943, yet managed to find time to earn a Ph.D. in plant morphology at the
University of Illinois in 1937. From 1943 through 1959 he was appointed as paleobotanist, then a
fossil fuels specialist, by the U. S. Bureau of Mines. In 1959 he was made the Director of the
Coal Laboratory of the U. S. Geological Survey, which was 1ocated on the campus of Ohio State
University in Columbus He remained there until the time of his death in 1978 at age 67.
He was an acknowledged leader of international repute in the difficult areas of taxonomy and
nomenc1ature of fossil plants and Paleozoic palynomorphs His publication (with Wilson and
Bentall) in 1944 was once the primer for the description of Paleozoic spores and generic groups.
Towards the end of his career, he spent several summers in the Antarctic and described the plant
fossils and coals he found there. He had a remarkable memory for details of numerous
paleobotanical and palynological subjects, and he always loved to discuss these matters with his
colleagues and friends.
William S. Hoffmeister took his A.B. and Ph.D. at Johns Hopkins University in Baltimore (1923-26).
He accepted a position as micropaleontologist with the Creole Petroleum Company in Venezuela
in 1926 and remained there until 1941. Probably due to the fact that the oil rich Maracaibo Basin
is principally composed of terrestrially derived sediments, it is presumed that he trained himself
in the stratigraphic aspects of
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palyno1ogy. From 1941 until 1946 he was employed as a stratigrapher for the Carter Oil
Company, then went with the Jersey Production Company, (=Exxon) through 1957, when he
turned to private consulting. Traverse (1988) indicates that Hoffmeister caused considerable
alarm among oil company palynologists when he received a patent for "Microfossil Prospecting
for Petroleum" in 1954. However, only a year later, he turned this patent over to the public
domain. His 1959 report of the occurrence of spores of the preserved oldest land plants in Libya
also created a stir among palynologists. He was the first person to receive honorary membership
in the
AASP (1975).
Robert H. Tschudy obtained three degrees in botany front the University of Washington (Seattle)
between 1932 and 1937. After a few years of teaching botany at the University of Wyoming and
Willamette University, he was hired in 1945 as Research Bio1ogist and Director of the
Palynology Laboratory of the Creole Petroleum Company in Venezue1a. He and his wife,
Bernadine (who was also a palynologist) returned to the United States in 1950 and established a
consulting laboratory near Boulder, Colorado. In 1962 both of the Tschudys were hired by the P
& S Branch of the U. S. Geological Survey in Denver. After retiring in 1973, Bob still
maintained an active research program right up to the time of his death in 1986. His textbook,
"Aspects of Palynology" (edited with R. A. Scott), appeared in 1969 and was generally well
regarded in the pa1ynologic community. His publications included palynofloras of the Late
Cretaceous and early Tertiary from the Rocky Mountains and the Mississippi Embayment pollen
of the Normapolles group and megaspore studies. A memoria1 article and complete bibliography
of Tschudy has been written by Douglas Nichols (1987).
Charles J. Felix, a native Kentuckian, spent four years in the U. S. Marine Corps before
matriculating at the University of Tennessee. After gaining his bachelor's degree there in 1949,
he attended Washington University in St. Louis for his graduate studies in paleobotany under the
direction of Henry Andrews. He earned the Ph.D. in 1954 with a dissertation on Carboniferous
plants found in coal balls. From 1954-56 he was a Research Associate with Jim Schopf in the
USGS Coal Laboratory at Ohio State University. From 1956 unti1 1981 he was employed as a
research geologist with the Sun Oil Company in Dallas, Texas. Next, he served as a Professor of
Geology at Abilene Christian University until his recent retirement. One of his major
contributions (with Patricia Paden Phillips) was a lengthy treatise on Cretaceous palynomorphs
from the Southeastern U. S. (1971).
Jane Gray completed her undergraduate training at Radcliffe College in 1951, then moved to the
University of California at Berkeley to work in paleobotany with Ralph Chaney Her Ph.D.
dissertation in 1958 was on Miocene palynomorphs from the Columbia Plateau of Oregon. After
teaching two years at the University of Texas, she joined the Geochronology Laboratory of the
University of Arizona as a Research Associate. However, in 1962 she was invited to direct the
Paleoeco1ogy Laboratory of the Museum of Natural History at the University of Oregon, where
she remains today.
Estella B. Leopold is the youngest of five offspring of the famous conservationist, Aldo S.
Leopold, who was a professor
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at the University of Wisconsin. Remarkably, all five siblings have become naturalists or
professional scientists, and three (Luna, Starker and Estella) have been elected to the National
Academy of Sciences (Carter, 1980). Estella got her bachelor's degree in botany at the University
of Wisconsin in 1948, then went west to gain her master's degree at the University of California
(Berkeley) in 1950. Next, she joined Paul Sears in the conservation program at Yale University,
where she earned her Ph.D. in 1955.
For the next 20 years she was attached to the P&S Branch of the USGS in Denver, where she
published numerous papers on Tertiary and Quaternary floras. Possibly one of her best known
contributions was the lengthy chapter on late Cenozoic palynology in the Tschudy and Scott
textbook. Another significant publication describes the Miocene palynomorphs recovered from
Eniwetok Atoll after atomic bomb tests there (1969).
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In 1975 she was named Director of the Quaternary Research Center at the University of
Washington in Seattle. Currently she is a Professor of Botany at that University.
William R. Evitt earned the Ph.D. in geo1ogy at Hopkins University in 1950. He taught at the
University of Rochester until 1956, when he received a 6-year appointment as a Research
Geologist with the Jersey Production Research Corporation (=Exxon). Desirous of returning to
academia, he joined Stanford University in 1962 as a Professor of Geology, where he
remained unti1 his recent retirement. Evitt is usually regarded as the most outstanding authority
in the United States on the taxonomy and morphology of dinoflagellates and acritarchs. Over
the years he has taught specia1 courses that trained numerous palynologists, particularly in the
oi1 industry, where these unique microorganisms have been shown to have remarkable value in
stratigraphic studies.
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April 26, 1962: Group photograph of the First International Conference
on Palynology University of Arizona (Photo by J.E. Canright that appeared in PALYNOS
article here replaced by Conference Photo)
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The First International Conference on Palynology
I have previously published a tribute to the recently departed Gerhard O. W. Kremp (1994); thus,
details of his life and career wil1 not be repeated here. However, I wish to emphasize Gerhard's
important role in organizing the First International Conference on Palynology, which was held at
the University of Arizona, April 23-27, 1962. When Gerhard joined the faculty there as a
Professor of Geochronology, he found as colleagues Paul Martin, Jane Gray, and Lucy
Cranwell. At that time, I believe this represented the largest and most distinguished assemblage
of palyno1ogists in a university setting. This group soon began to formulate plans for an
international meeting of palynologists. The General Chairman appointed by the university for
this meeting was Terah L. Smiley, a dendrochronologist, who was the Director of the
Geochronology Laboratory at that time. Gerhard Kremp was selected as Program Chairman and
Paul Martin was put in charge of field trips. Because of his numerous contacts with European
palynologists, Kremp succeeded in getting such wel1 known persons as Gunnar Erdtman
(Sweden), Sir Harry Godwin (UK), and Robert Potonie (Germany), not only to attend this
conference in the Sonoran Desert, but also to give the main
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lectures at the opening Plenary Session (see figure at the top of Page 6, showing these speakers in
the order listed above).
Two other papers at this plenary session attracted considerable attention of the media. Elso
Barghoorn first described the many unique microfossils that he and Stanley Tyler had recently
discovered in the Gunflint Formation of Precambrian age. George C1aus and Bartholomew Nagy
next described supposed primitive algae and flagellates they had found in meteorites (Despite the
furor raised by these claims, it was later shown that the meteor fragments had been contaminated
by earth borne microorganisms).
Although originally there were 235 registrants, the last minute withdrawa1 by 33 Soviet
palynologists created numerous gaps in Kremp's well organized program. The rumored
explanation (never corroborated) for the defection of the Soviet palynologists, was that the Soviet
authorities were upset because the U.S.-issued visas restricted travel outside the Tucson area,
because the Department of Defense had severa1 guided missile silos around the city at that time.
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Part of the front page from the April 18, 1962 issue of the
University of Arizona schooll newspaper discussing the 1st International Palynological
Congress that was hosted at the University by the Geochronology Laboratory. Shown left
to right are: Drs. Erdtman, Godwin and Potonie. (Provided by J.E. Canright)
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Practically all of the American palyno1ogists discussed in this article were Chairmen of the 21
wide ranging sessions on the program. Because these meetings were so enthusiastically
endorsed by the delegates, Norman Hughes (University of Cambridge) chaired a special meeting
to discuss continued internationa1 cooperation among palynologists, an Internationa1
Palynological Conference Committee was formed, with Frank Staplin (Calgary) as chairman.
This committee's task was to insure that a second palynology conference would be convened 4-5
years later (McGregor, 1987). Obviously, these plans bore fruit when the 2nd IPC was held in
Utrecht, The Netherlands, in 1966 with 270 registrants.
Submitted by:
Dr. James E. Canright
President IFPS
Literature cited:
Canright, J. E. 1953.
The comparative morphology and relationships of the Magnoliaceae II.
Significance of the pollen. Phytomorphology, Delhi, 3:355-365
-----1962.
(Abst.) Comparative morphology of pollen of Annonaceae. Pollen et Spores 4:338.
-----1984.
What's in a name? Palynos 7(2):1-2.
-----1994.
G.O.W. Kremp, 1913-1994. Palynos 17(2):5-6.
Carter, L. J. 1980.
The Leopolds: a family of naturalists. Science 207:1051-1055.
Cranwell, Lucy M. 1964.
Ancient Pacific floras - the pollen story. Univ. Hawaii Press,
Honolulu, ll4 pp.
Cross, A. T. (ed.) 1964.
Palynology in oil exploration: a symposium. S.E.P.M. Spec. Publ. no.ll, 200 pp.
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Heusser, C. L. 1971.
The pollen and spores of Chile. Univ. Arizona Press, Tucson, 167 pp .
Hoffmeister, W. S. 1959.
Lower Silurian plant spores from Libya. Micropaleontology 5(3): 331-334.
Hopping, C. A. 1967.
Palynology and oil explanation Rev. Palaeobot. Palynol. 2:23-48.
Leopold, Estella B. 1969.
Miocene pollen and spore flora of Eniwetok Atoll, Marshall Islands.
USGS Prof. Paper 260 II:ll33-ll82.
Manten, A. A. 1967.
Lennart von Post and the foundation of modern palynology. Rev. Palaeobot Palynol. 1:ll-22.
McGregor, D. C. 1987.
Palynnlogy---the international connection. Palynos 10(1):6-8.
Nichols, D. J. 1987.
Robert H. Tschudy, a memorial, Palynos 10(1):6-8.
-----1994.
The IPC logo. Palynos 17(1): 1.
Paden Phillips, P. and C. J. Felix. 1971.
A study of the Lower and Middle Cretaceous spores and
pollen from the Southeastern United States. Pollen et Spores 13:279-348; 447-473.
Schopf, J. M., L. R. Wilson, and R. Bentall. 1944.
An annotated synopsis of Paleozoic spores
and the definition of generic groups. Ill. Geol. Surv. Rept. Invest. 91, 72 pp.
Traverse, A. 1955.
Pollen analysis of the Brandon Lignite of Vermont. U. S. Bur. Mines Rept. of
Invest. 5151.
----1974.
Paleopalynology 1947-1972.
Ann. Mo. Bot. Gard. 61:203-236.
----1988.
Paleopalynology. Unwin Hyman Co., Boston, 600 pp.
Traverse, A. and H. J. Sullivan. 1983.
The background, origin, and early history of the American
Association of Stratigraphic Palynologists. Palynology 7: 7-17
Tschudy, R. H. and R. A. Scott (eds.) 1969.
Aspects of palynology. Wiley Interscience, New York, 510 pp.
Wodehouse, R. P. 1935.
Pollen grains. McGraw Hill Book Company, New York, 574 pp. & 14 plates.
Wright, H. E. and D. G. Frey (eds.) 1965.
The Quaternary of the United States. Princeton
University Press, Princeton, N.J. 922 pp.
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