Bøger:
* Botanik i Californien (med John Torrey og Asa Gray, 1876)
* Filices Americanae (med John Torrey, 1878-1880)
* The Bregns of North America (med James Walter Fewkes, 1879-1880)
* En liste over planter i nærheden af New Haven (1879)
* En lærebog i systematisk og økonomisk botanik (1879)
* The Bregns of North America (med James Walter Fewkes, 1879-1880)
* Bregnerne i USA og det britiske Nordamerika (1880)
* The Ferns of North America (med James Walter Fewkes, 1881)
* The Illustrated Handbook of Ferns of the United States and British North America (med James Walter Fewkes, 1882)
* The Wild Flowers of Colorado (med Sereno Watson, 1883)
* The Ferns of the United States and Canada (med James Walter Fewkes, 1884)
* Supplement til Bregnerne i Nordamerika (med James Walter Fewkes, 1884)
* The Wild Flowers of Maine (med Sereno Watson, 1885)
* The Ferns of the United States and British North America (med James Walter Fewkes, 1885)
* The Ferns of North America (med James Walter Fewkes, 1887)
* De vilde blomster i det nordøstlige USA (med Sereno Watson, 1887)
* The Ferns of North America (med James Walter Fewkes, 1888)
* The Ferns of North America (med James Walter Fewkes, 1890)
* The Ferns of North America (med James Walter Fewkes, 1891)
* The Ferns of North America (med James Walter Fewkes, 1893)
* The Ferns of North America (med James Walter Fewkes, 1894)
* The Ferns of North America (med James Walter Fewkes, 1896)
* The Ferns of North America (med James Walter Fewkes, 1898)
* The Ferns of North America (med James Walter Fewkes, 1900)
* The Ferns of North America (med James Walter Fewkes, 1902)
* The Ferns of North America (med James Walter Fewkes, 1904)
* The Ferns of North America (med James Walter Fewkes, 1906)
* The Ferns of North America (med James Walter Fewkes, 1908)
* The Ferns of North America (med James Walter Fewkes, 1910)
* The Ferns of North America (med James Walter Fewkes, 1912)
* The Ferns of North America (med James Walter Fewkes, 1914)
* The Ferns of North America (med James Walter Fewkes, 1916)
* The Ferns of North America (med James Walter Fewkes, 1918)
* The Ferns of North America (med James Walter Fewkes, 1920)
* The Ferns of North America (med James Walter Fewkes, 1922)
* The Ferns of North America (med James Walter Fewkes, 1924)
* The Ferns of North America (med James Walter Fewkes, 1926)
* The Ferns of North America (med James Walter Fewkes, 1928)
* The Ferns of North America (med James Walter Fewkes, 1930)
* The Ferns of North America (med James Walter Fewkes, 1932)
* The Ferns of North America (med James Walter Fewkes, 1934)
* The Ferns of North America (med James Walter Fewkes, 1936)
* The Ferns of North America (med James Walter Fewkes, 1938)
* The Ferns of North America (med James Walter Fewkes, 1940)
* The Ferns of North America (med James Walter Fewkes, 1942)
* The Ferns of North America (med James Walter Fewkes, 1944)
* The Ferns of North America (med James Walter Fewkes, 1946)
* The Ferns of North America (med James Walter Fewkes, 1948)
* The Ferns of North America (med James Walter Fewkes, 1950)
* The Ferns of North America (med James Walter Fewkes, 1952)
* The Ferns of North America (med James Walter Fewkes, 1954)
* The Ferns of North America (med James Walter Fewkes, 1956)
* The Ferns of North America (med James Walter Fewkes, 1958)
* The Ferns of North America (med James Walter Fewkes