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COLLECTION Identifier: gra00032

Thomas Potts James manuscripts and notes

Scope and Content

This collection falls into two main categories: materials pertaining to the article "Descriptions of Some New Species of North American Mosses" published in “Proceedings of the American Academy of Arts and Sciences” in 1879 and miscellaneous notes.


  • circa 1878


Conditions Governing Access

The collection is available by appointment for research. Researchers must register and provide one form of valid photo identification. Please contact for additional information.


0.1 linear feet (3 folders)


Thomas Potts James was born on September 1, 1803 in Radnor, Pennsylvania to Isaac and Henrietta James (née Potts). The family moved to Trenton, New Jersey when James was nine years old. He and his older brother, John, both intended to enter Princeton College, but the family’s financial circumstances prevented them from doing so. Instead, both studied pharmacy and eventually opened a pharmacy together in Philadelphia in 1831.

Potts married Isabella Batchelder in December 1851. The couple lived briefly in New Jersey before settling in Philadelphia; they had four children.

James likely became interested in botany through its application to medicine. He studied the local flora in his free time and soon turned his focus to cryptogamic botany and bryology in particular. In 1866 James left the pharmacy to devote his time to bryology and the following year moved with his family to Cambridge, Massachusetts. James began corresponding with Swiss bryologist, Leo Lesquereux, in 1848. Their collaboration yielded several publications, including a “Manual of the Mosses of North America,” published two years after James’s death with final editing and compilation work carried out by Sereno Watson at the Gray Herbarium.

James’s working life spanned the period of government-sponsored exploration of the continent and he contributed catalogues of mosses for reports on the Clarence King and Wheeler Surveys. He was a member of several scientific societies and a prolific correspondent, exchanging letters with many prominent bryologists and botanists of the day. James suffered a stroke and died on February 22, 1882. He is buried at Mt. Auburn Cemetery in Cambridge, Massachusetts.


Gozzaldi MIJ. 1903. Thomas Potts James. Bryologist. 6(5):71-74.

Rothrock JT. 1882. Biographical sketch of Thomas Potts James. Proc. Amer. Philos. Soc. 20(111):293-297.


The provenance of this collection is unknown. It was likely acquired by Sereno Watson to aid his revision of “Mosses of North America” and remained at the Gray Herbarium after his death in 1892.

Related Materials

Other related material at the Botany Libraries, Harvard University Herbaria: Asa Gray correspondence files, 1832-1892; Thomas Potts James papers, 1843-1984, bulk 1855-1881.

James’s personal herbarium is deposited in the Farlow Herbarium.

James's microscope, purchased in Leipzig in 1878 and presented to the Farlow Herbarium by his daughters in 1925 was transferred to the Collection of Historical Scientific Instruments at Harvard University.

James, Thomas Potts, 1803-1882. Thomas Potts James manuscripts and notes, circa 1878: A Guide.
Botany Libraries, Gray Herbarium Library, Harvard University.
Description rules
Language of description

Repository Details

Part of the Botany Libraries, Gray Herbarium Library, Harvard University Repository

The Harvard University Herbaria houses five research libraries that are managed collectively as the Botany Libraries. The Gray Herbarium Library specializes in the identification and classification of New World plants with emphasis on North American plants. The Archives of the Gray Herbarium houses unique resources including personal papers, institutional records, field notes and plant lists, expedition records, photographs, original artwork, and objects from faculty, curators, staff, and affiliates of the Gray Herbarium.

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