Evans, Alexander William
EVANS, ALEXANDER WILLIAM
Alexander Evans died, at the age of ninety-one, the undisputed leader in two unrelated areas of botanical research. After achieving eminence as a hepaticologist, he turned to lichenology and made contributions of equal importance to that field. His mysterious withdrawal from hepaticology, at an advanced age, and his youthful approach to a new interest have continued to charm and intrigue practitioners of both specialties.
Evans was the youngest of seven children of William A. and Maria Ives Beers Evans. His father, a planing mill operator, died in 1880, whereupon the family moved to New Haven. Evans attended public high school there and continued his education at Yale University, where he received the Ph.B. (1890), M.D. (1892), Ph.D. (1899), and D.Sc. degrees (1947),
After medical school Evans served a two-year internship at the New Haven City Hospital, but he never practiced medicine. As early as 1888, his first year in college, he had been influenced by Daniel Cady Eaton to take up the study of bryophytes. During undergraduate and medical training he added more than twenty liverworts and a good number of Sphagna to the known flora of Connecticut and also found, in New Hampshire, a curious moss that Eaton described as new. (This moss, Bruchia longicollis, has not been collected since then.) From 1891 to 1893 Evans published four papers on liverworts (of Hawaii, Connecticut, Virginia, West Virginia, and Patagonia), including excellent descriptions and illustrations of seven new species. He demonstrated such competence that it is not surprising that he decided to give up medicine altogether. In the fashion of the time, he went to Germany in the fall of 1894 to study botany at the universities of Berlin and Munich.
In the following spring Evans was summoned by cablegram to return to Yale to fill the vacancy left by the death of Eaton. He served there for the rest of his life, as instructor (1895-1901), assistant professor (1901-1906), Daniel Cady Eaton professor (1906-1936), and professor emeritus (1936-1959). He was chairman of the department of botany for many years.
On his return Evans prepared himself to meet the requirements of a Ph.D. degree. Tradition has it that as sole preceptor of botany, he rejected his first dissertation (a revision of North American species of Frullania), whereupon he successfully defended a second, entitled “The Hawaiian Hepat-icae of the Tribe Jubuloideae.”
For years Evans spent part of each summer in Europe, visiting herbaria and searching for literature. He attended several international botanical congresses at Paris (1900), Vienna (1905), and Brussels (1910).
Evans was not skilled as an administrator, and as a teacher he was not able to handle large groups of uninterested students. He worked well, however, with individual students who showed motivation; and two of his graduate students, Margaret Fulford and Hempstead Castle, became hepaticolo-gists of note.
Evans’ taxonomic acumen was based on a complete familiarity with plants. Extensive field study gave authority to his monumental publications on Cladonia, to many papers on liverworts, and to a book, The Bryophytes of Connecticut (1908), written with George Nichols. The last, modest in size and format (and selling for thirty cents), appeared at a time when there were no convenient means of identifying bryophytes in any part of North America. It is still useful because of well-constructed keys to genera and species representative of most of eastern North America. Evans also collected extensively elsewhere in New England and along the eastern seaboard, and made short visits to Cuba, Jamaica, Puerto Rico, Panama, Venezuela, and Colombia.
Evans’ work on hepaticology, by no means outmoded now, is admirable because of his effective use of morphological detail in interpreting relationships. As a teacher he had offered instruction, at one time or another, in virtually every discipline of plant science; but it was to morphology that he was most devoted. A product of the classical school of morphology, he contributed much in the way of structural and developmental detail, and gave phylogenetic meaning to a mass of information already in the literature. His account of reduction as a prevailing trend in liverwort evolution and his scheme of classification based on that trend reflect a thoroughly modern point of view.
In 148 articles on liverworts, Evans described seven genera and more than 135 species new to science. His papers were thorough and even encyclopedic in documentation, yet concise and readable. (After Evans’ retirement, M. L. Fernald, editor of Rhodora and master craftsman at writing, published a lament that few botanists could write as well as the “late” Alexander Evans —who was active in publication long after Fernald’s demise.) Evans’ taxonomic contributions were enhanced by unusually graceful and accurate drawings.
Most of Evans’ papers were floristic accounts — more than half on North America, a quarter on Latin America, and a goodly number on the exotic floras of Hawaii, Sumatra. Japan, and elsewhere. His “Notes on New England Hepaticae” (1902-1923) and “Notes on North American Hepaticae” 1910-1923) are among the most informative reference sources available to American workers. His “Hepaticae of Puerto Rico” (1902-1911) is essentially a monograph of the Lejeuneaceae. Evans contributed monographs on numerous families of thalloid liverworts to the North American Flora and published many generic revisions—of Marchantia, Dumortiera, Riccardia, Metzgeria, Symphyogyna, Hymenophytum, Acromastigum, Herberta, Frullania, and Lejeunea.
Evans intended to go a further step and prepare a comprehensive liverwort flora of North America. That project was never completed because of the rash and precipitate appearance of T. C. Frye and Lois Clark’s Hepaticae of North America, a warts-and-all synthesis from the literature, and even more because of Evans’ late-born interest in Cladonia. He began to collect lichens in Connecticut in 1924, methodically filling in county and township records. His specimens, mostly named by G. K. Merrill, were recorded in Catalogue of Connecticut Lichens in 1926, with additions in 1927. Evans produced a Cladonia flora of the state in 1930: and for the next thirty years he specialized in that large and difficult genus and only rarely bothered with other lichens or hepatics.
Evans was not interested in popularizing Cladonia, attractive as the genus is, and his papers can be appreciated only by a specialist. Although he described fewer than ten new species, he made Cladonia the world’s best-known lichen genus. His major achievement was the successful use of chemistry to define species, employing microchem-ical methods that Yasuhiko Asahina had only recently applied to Cladonia in Japan. Heinrich Sandstede, in a supplement to E. A. Vainio’s monograph on Cladonia, had given notice of these methods in 1938; but Evans, in 1943, explained and exemplified them in a particularly effective way. These microchemical methods provided the means to extract substances from mere bits of thalli and to identify them microscopically by their crystalline structure, thus enabling a taxonomist to demonstrate distinctive substances quickly and easily, without needing the knowledge or methods of the organic chemist. Evans had a narrow concept of species, based on familiarity with plants gained from unhurried study. His knowledge of Cladonia was so intimate that he could recognize many taxa that less critical workers might have overlooked, and in some instances he was able to correlate morphological subtlety with chemical difference. His conclusions regarding chemical taxa were so logical and so convincing that chemo-taxonomy has become essential in the study of Cladonia and has been applied with outstanding success to numerous other genera of lichens,
Evans published twenty-five papers on lichens. including important accounts of the Cladoniae of Connecticut. New Jersey, Vermont. Florida, and the Carolinas. With P. R. Burkholder and others he wrote two papers reporting antibiotic properties of lichens—another area of pioneering activity.
Evans’ Cladonia herbarium of nearly 40,000 specimens is housed at the Smithsonian Institution, and his hepatic herbarium of more than 30,000 specimens is kept at Yale.
Evans was on the editorial board of Bulletin of the Torrey Botanical Club from 1907 to 1934 and served as editor from 1914 to 1924. He was associate editor of Bryologist for many years, secretary of the Connecticut Academy of Arts and Sciences (1897- 1903), vice-president of the Botanical Society of Ameria (1911), a fellow of the American Association for the Advancement of Science, and honorary member of the Sullivant Moss Society. In 1947 he received an honorary D.Sc. degree from Yale University. Evans was invited to serve as honorary president of the section on lichenology at the Eighth International Botanical Congrèss meeting at Paris in 1954, but was unable to attend. On the occasion of the golden jubilee of the Botanical Society of America, in 1956, he was given a certificate of merit as one of fifty who had made outstanding contributions to botanical science.
Evans married Phoebe Whiting of New Haven in 1914. They had three daughters: Margaret, Janet, and Allison. (His daughter Margaret was killed, reportedly by an estranged husband, in the Evans’ home in the summer of 1954. Difficult as this was, and at his age, Evans found strength to bear his grief and continue his work with quiet dignity.)
In October 1959, at the age of ninety-one. he fell and broke his hip. He submitted to an operation and was making good progress toward recovery when he contracted pneumonia and died. He was survived by his wife, two daughters, and seven grandchildren. A private service was held in his home and a memorial service at St. John’s Episcopal Church.
Lewis Anderson wrote in reminiscence:
His quiet and genuine modesty, his sense of humility, his continual and almost overpowering regard for others, his brilliant but often subtle sense of humor, and his tremendous personal integrity formed the hard core of his lovable personality. These traits seemed almost to be etched in his face in later years. Somewhat heavy of jowl and for many years afflicted with a slight but very noticeable palsy he had a way of looking at one so that his face would literally light up, and his eyes would twinkle and somehow communicate a mischievous quality that one cannot forget [Bryologist, 63 (I960). 87-88].
Evans was neither dynamic nor forceful. He had a mild voice, a gentle manner, and a warm personality, as well as strong cultural interests and a complete indifference to financial concerns. His dignity sometimes expressed itself in incongruity. He rode a bicycle but wore a sober hat in keeping with his age and position. In the field he was careful to wear a jacket and tie in combination with disreputable pants and shoes. Evans was “half decent” in the laboratory too. His articles were models of precision and his herbaria carefully tended, but his office was a shambles. As an old man he had astonishing endurance. In the field, even though he was decidedly paunchy and forbidden by his doctor to collect in hilly country, he could make his way surely over any other terrain, unmindful of fatigue or difficulties underfoot. His palsy made it difficult and tiring to use a microscope, but he worked — productively—six or seven hours nearly every day until the end of his life.
Bibliographies listing Evans’ work in bryology have been provided by Schuster and in lichenology by Hale (see below).
For secondary literature, see L. E. Anderson, “Personal Reflections on Alexander W. Evans,” in Bryologist,63 (1960), 84-88, with photograph; M. E. Hale, “Alexander W. Evans and Lichenology ibid.,81-83, with bibliography; and ’Alexander William Evans,” in Bulletin of the Torrey Botanical Club, 87 (1960). 354-356. with photograph; H. A. Miller, reminiscences. in Revue bryologique et lichénulogique n.s. 29, nos. 1-2 (1960), 140; G. E. Nichols, “Alexander William Evans, Hepaticologis” in Annates biyahgici, II (1938). 1-5; J. R. Reeder, “Alexander William Evans (1868-1959).” in Taxotu9 (I960), 168- 169, with photograph; and R. M. Schuster, “Alexander W. Evans—an Appreciation,” in Bryoiagisr,63 (1960), 73-81, with photographs and bibliography; and “Alexander W. Evans (1868-1959),” in Revue bryologique et lichénulogique n.s. 29. nos. 1-2 (1960), 132-139, with photograph and bibliography.