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History of the Ecological Sciences, Part 33: Naturalists Explore North America, mid‐1780s–mid‐1820s

2009; Ecological Society of America; Volume: 90; Issue: 4 Linguagem: Inglês

10.1890/0012-9623-90.4.434

2327-6096

Frank N. Egerton,

Species Distribution and Climate Change

Click here for all previous articles in the History of the Ecological Sciences series by F. N. Egerton Natural history explorations, we have seen in Parts 22, 25, 27, and 32 (Egerton 2006, 2007, 2008, 2009b), often led to publications that, in retrospect, contain ecological observations. Humboldt set an excellent example by measuring many environmental variables during his explorations; later explorers never measured as many variables as he, but some of them recorded temperature, precipitation, and barometric pressure. The exploration literature of the late 1700s and early 1800s increased steadily in volume. There are good introductions to naturalist-explorers in North America from mid-1780s to mid-1820s that are more comprehensive than this part of my history. They include bibliographies (Meisel 1924–1929, 1967, Wood 1931, Wagner et al. 1982, Harkányi 1990, Stanton 1991), histories of American science (Smallwood and Smallwood 1941, Struik 1948, Dupree 1957, Daniels 1968, Greene 1984, Porter 1986, Welch 1998), biographical dictionaries (Gillespie 1970–1980, Sterling et al. 1997, Garraty and Carnes 1999), a biographical history of American science (Jaffe 1958), a history of scientific societies (Oleson and Brown 1976), accounts of natural history exploration (Peattie 1936:201–260, Ewan 1950, Goetzmann 1959, 1967, 1986, Savage 1970, 1979, Hanley 1977, Ewan and Ewan 1981, Spencer 1986a, b, Viola 1987, Evans 1993, Fishman 2000, Moring 2002, Beidleman 2006:4–70), of botanical exploration (McKelvey 1955:3–280, Leroy 1957, Thomas 1979:7–10, Reveal 1992), and of ornithological exploration (Allen 1951:526–569, Welker 1955:16–58, Fischer 2001:8–14). The achievements discussed here give some idea of what was being accomplished simultaneously by other naturalists in North and South America, Africa, Asia, Australia, and various islands. Although the American War of Independence marks a transition from colonial to independent science, after independence some Americans continued to travel to Europe for some or all of their science education, and some European naturalists continued to explore in America. Our first two naturalists were a French father and son. André Michaux (1746–1803 [not 1802; Taylor and Norman 2002:xiv]) was born at a royal farm managed by his father near Versailles. He attended a boarding school for four years and studied both agriculture and Latin. He was orphaned at age 20, and for a while he and a brother managed the farm. He married in 1769, and in 1770 his wife died in childbirth. François André Michaux (1770–1855) saw little of his busy father during his first 15 years. André Michaux attracted the interest of two aristocratic patrons and began studying botany in 1777. In 1779 he moved to Paris to continue his studies at the Jardin du Roi (Savage and Savage 1986:6–10, Tino 1997, MacPhail 1999a, Taylor and Norman 2002:10–14). In 1780 he accompanied Lamarck on a trip to the Auvergne and the Pyrenees to collect plants, birds, insects, and minerals (Ewan 1974:366). In 1782 he accompanied a French diplomat to the Turkish Empire, where he collected seeds and plants for three years, which periodically he sent to Paris. He was also interested in animals and fossils. He traveled as far east as the region south of the Caspian Sea. Two letters to his son and a travel journal remain unpublished but were available to his biographers (Coats 1969:22–25, Savage and Savage 1986:16–33). Michaux returned to Marseilles on 23 May 1785, and on 1 September he departed on a collecting trip to America. This time he took his son François, a servant, and a gardener, Pierre Paul Saumier (1751–1818). They reached New York on 13 November, and in March 1786 Michaux bought a 29- acre farm, to use as a nursery, in New Jersey, six miles from New York City (Robbins and Howson 1958). This farm-nursery was run by Saumier, who used half of it as a farm to supplement his pay; he never returned to France. On 19 April 1887 Michaux reached Charleston, South Carolina and bought a farm of 111 acres for the same purpose (or he may have bought the farm in 1886, before he arrived [Coker 1911:66–67]). He remained in America until 13 August 1796. During those 11 years he went on numerous brief explorations and eight long expeditions, plus a trip to the Bahamas in 1789. François accompanied him on some expeditions, but possibly on 5 February 1790 François sailed back to France to study medicine. He carried many live plants and chests of seeds (Savage and Savage 1986:107, Wassong 1997, MacPhail 1999b). In addition to studying medicine, he studied botany at the Jardin des Plantes (Savage and Savage 1986:164). André Michaux kept travel journals with observations made from Florida to almost Hudson's Bay and from the Atlantic to the Ohio and Mississippi rivers, during which he discovered more than 300 plant species unknown to science (True 1937:313, Coats 1969:282–283, 285–289, Fishman 2000:67–92). After he returned from near Hudson's Bay to Philadelphia in December 1792, he discovered that the French Republic had not sent funds he had anticipated, and he turned to friends in the American Philosophical Society with a proposal for them to fund his exploration of the Missouri River (Ewan and Ewan 2007:498–499). A plan was underway, with Jefferson having written detailed instructions for him (Jackson 1981:75–78), when the French ambassador, Edmond Charles Genet, hijacked the trip and sent Michaux into Kentucky instead, on a wild imperialistic scheme that could not succeed (Savage and Savage 1986:124–175). Yet Michaux still observed and collected plants on that journey. When he sailed for home in 1796, he suffered shipwreck off the coast of the Netherlands and lost his journals for the period November 1785 to August 1787 (Savage and Savage 1986:161–162). His remaining American journals would be donated in 1815 by François to the American Philosophical Society in recognition of the assistance given by that society to both father and son. Botanist Charles S. Sargent published it in French in October 1888 (for an 1889 volume). In 1904–1905 Reuben G. Thwaites published his own English translation of pages 91–101 and 114–140, from the years 1793–1796 (MacPhail 1981). …we arrived at the shore of the stream whose water was so agreeable and beautiful. It is situated only one-half a mile from the salt water river [Salt River] the water of which is just as bad as the water of the little river is good. I experienced furthermore the satisfaction of collecting at only eighty toises distant the Illicium…this shrub is found in places where the Magnolia grandiflora, the Annona grandiflora, Olea Americana, Ilex cassine etc. etc. grow but more particularly where one also finds Aralia spinosa and a Grass called “Canes” which grows to ten feet in height which always indicates a good but sandy and cool soil. Some of his observations are merely inventory, as eight years later, on 1 January 1796 (Michaux 1888:129, 1904:82–83): Wind from the north; frost; the river rose one inch during the night. In the vicinity of Little River, the country has hills scattered here and there. Soil clayey, very rich mould, rock consisting of Silex very slightly ferruginous. Blue limestone. Animals: raccoons, dwarf deer, opossums, buffaloes, bears, grey squirrels, beaver, otter, muskrats (these [last] three species very rare). Birds: Ravens, owls of the large species, cardinals, blue jays; green parroquets with yellow heads of the small species; jays with red heads and throats. Trees and plants: Liriodendron; Liquidambar; yellow chestnut oak, red oak; Annona; hornbean. At other times he commented on a particular species, as in this discussion of Arundinaria macrosperma Mich., presumably the “Canes” of his Florida journal, written 29 February 1796 (Michaux 1888:135, 1904:94–95): This species of grass which grows abundantly in many places which have not been settled, is destroyed when completely eaten by cattle; swine also destroy it by rooting in the earth and breaking the roots. The stalk is sometimes as thick as a goose quill, but in the rich lands bordering on the rivers and between the mountains, some stalks are as much as 2 and even 3 inches in diameter; the height is sometimes from 25 to 30 feet. This grass is ramose but it seldom bears fruit in the territory of Kentucky, in that of Tenesee or in that of the Carolinas. This grass begins in the southern and maritime portion of Virginia. Further South as in the Carolinas, in the Floridas and in Lower Louisiana, this grass is found in abundance. André Michaux had left a monarchial France in 1785 and returned to a turbulent republic in 1796. Although he found the political change agreeable, the Republic did not honor the financial obligations to him the monarchy had incurred, and he suffered financial hardships. Consequently, although he spent time working on both the live and dried specimens and seeds he had collected for the government, the circumstances were unfavorable for completing his history of American oaks and his two-volume Flora Borali- Americana (Savage and Savage 1986:167–170). Therefore, in 1799 he accepted an invitation to be a naturalist on a voyage of exploration that eventually went to Australia. This was the same expedition that both Humboldt and Bonpland had wanted to join but had given up on because of delays (Egerton 2009). On 19 October 1800, the expedition sailed from Le Harve under Nicolas Thomas Baudin (1785–1803), not under Louis Bougainville, who had been its early planner. Its staff included 3 botanists, 5 zoologists, 2 mineralogists, 3 artists, 5 gardeners, and 2 geographers. (Horner 1988:3). Michaux left the expedition at Île de France (Mauritius), and a historian of the expedition thinks he may have intended to do so from the start (Horner 1987:73–74, 119). Nine months later Michaux sailed to Madagascar, where he died from a fever (Savage and Savage 1986:177–179). François Michaux, a faithful son, saw to the publication of his father's books on American oaks and flora (MacPhail 1981). André Michaux's Flora Borali-Americana (two volumes, 1803) was the first comprehensive flora for eastern North America. The text was produced in Latin by Louis Claude-Marie Richard and was limited to descriptions, with brief comment on range, and with many species illustrated (Fig. 1). None of André Michaux's travel observations were incorporated into the accounts. The account quoted above of Arundinaria macrosperma would have enriched the brief unillustrated account of this species in Flora Boreali-Americana (1803, I:73–74, 1974). André Michaux's herbarium is in the Muséum d'Histoire Naturelle in Paris (Stafleu and Cowan 1976–1988, III:456–459), and in 1838 Asa Gray found in it a specimen representing a genus and species from the mountains of the Carolinas that had been omitted from the Flora. Gray named it Shortia galacifolia; wild specimens were rediscovered in 1877 (Sargent 1886:472). Michaux had found it in what is now Oconee County, South Carolina, and his journal entries from his two trips into that area, 1787 and 1788, are now translated into English and annotated with maps and photographs by Margaret Seaborn (1976). The Canadian botanist Ovide Brunet (1864) used Michaux's notes on herbarium sheets to determine the route he had taken toward Hudson's Bay, and Jacque Rousseau (1948) has discussed further a portion of this journey, with two maps. Dalibarda violaeoides. A. Michaux 1803: I, plate 29, 1974. …a variety of the red oak, the acorn of which is nearly round; the white oak, quercus alba; and, among the different species or varieties of nut trees, the juglans tomentosa, or mocker-nut, and the juglans minima, or pig-nut. In the low and marshy places, where it is overflowed almost all the year, we found the juglans-hickory, or shell-barked hickory; the quercus prinus aquatica, which belongs to the series of prunus and is not mentioned in the History of Oaks. The valleys are planted with ash trees, palms, cornus florida's poplars, and quercus tinctoria, known in the country by the name of the black oak. The quercus tinctoria is very common in all the northern states; it is likewise found to the west of the Alleghany mountains, but is not so abundant in the low part of Georgia and the two Carolinas. In Philadelphia he met William Bartram, Charles W. Peale, and other naturalists. In the Pennsylvania countryside he commented on the many rattlesnakes seen killed along the road (F. Michaux 1904:146). He traveled to Pittsburgh where “the air is very salubrious,” intermittent fevers were unknown, and the people were not tormented by mosquitoes in summer. People in Pittsburgh built large vessels for the Ohio River and used a variety of trees, all of which he listed. Michaux also commented on the extraction of sugar from sugar maples (F. Michaux 1904:157, 160, 163). Michaux sailed from Charleston about 1 March 03 for Bordeaux, laden with plants and seeds. He had previously sent others to Paris (Savage and Savage 1986:257–259). During two years in Paris he prepared his travel journal for publication (1804; English, 1805) and studied how well American trees that he and his father had sent or brought from America were growing in France. The outcome of the latter study was his Memoire sur la naturalization des arbres forestiers 1805. He then returned to America in 1806–1808 to prepare his well-illustrated natural history of eastern North American trees (three volumes, 144 plates, 1810–1813, English, 1817–1818), the outcome of three multiple-year trips to America (Wassong 1997, MacPhail 1981, 1999b). …the white maple is found on the banks of such rivers only as have limpid waters and gravelly bed, and never in forests where the soil is black and miry. These situations, on the contrary, are so well adapted to the red maple that they are frequently occupied by it exclusively. Hence the last mentioned species is common in the lower parts of the Carolinas and of Georgia, for as soon as the rivers, in descending from the mountains toward the ocean, reach the low country they begin to be bordered by miry swamps covered with cypress, black gum, large tupelo, etc. The Michaux, father and son, were remarkably persistent private explorers in America. Climate, as characterized by the thermometer, by the proportion of rainy, cloudy, & clear days, by lightning, hail, snow, ice, by the access & recess of frost, by the winds prevailing at different seasons, the dates at which particular plants put forth or lose their flower, or leaf, times of appearance of particular birds, reptiles or insects. On July 5 Lewis left for Pittsburgh, where he had a special boat built and began to recruit men for the expedition. Clark received Lewis' letter on 18 July, and the next day wrote back his acceptance (Jackson 1962:110–111). Clark also began recruiting men for the expedition. In early September, Lewis and his men sailed and rowed down the Ohio and on October 15 collected Clark along the way. They continued on to the Mississippi, and then traveled upriver to St. Louis. They spent the winter of 1803–1804 across the river from the city. The two leaders worked well together, and Clark proved to be a skilled map maker (Allen 1975, Sterling 1997a, Steffen 1999, Foley 2004, Jones 2004). Spanish and French explorers had previously explored the Missouri (Nesatir 1952), but little, if any, of their findings were known to the Americans. In the spring they struggled up the Missouri and spent the winter of 1804–1805 beside the Mandan Indians (now in North Dakota). On 7 April 1805, Lewis and Clark sent their writings and collections of specimens made thus far downriver to St. Louis, New Orleans, and on to Washington. Included were four live magpies, a sharp-tailed grouse, and a live prairie dog; one magpie and the prairie dog survived the trip, and Jefferson sent them to Charles Willson Peale for his museum (Cutright 1969:375–376, Sellers 1980:186). Then the explorers crossed the Rocky and Cascade mountains and descended the Columbia River to the Pacific. They spent the winter of 1805–1806 at the mouth of the Columbia River at their Fort Clatsop. On 23 March 1806 they departed Clatsop and reached St. Louis on September 23 (Moulton 2003). There is an impressive literature on the natural history of the Lewis and Clark Expedition (Johnsgaard 2003b, Tubbs and Jenkinson 2003). Raymond Burroughs' The Natural History of the Lewis and Clark Expedition 1961 is limited to their records on vertebrates. Excepting a lengthy introduction, the book is a collection of quotations from their journals arranged into chapters on the different groups of vertebrates, with brief editorial comments. Paul Cutright's Lewis and Clark: Pioneering Naturalists 1969, 2003 is very different. Its chapters follow the expedition from St. Louis to the Pacific and back. It is a history that discusses plants as well as vertebrates, has some contemporary illustrations, and appendixes on the discoveries of plants, animals, locations, and maps. Paul Johnsgard's well-illustrated Lewis and Clark on the Great Plains (2003a) is more restricted geographically than the previous two and is correspondingly briefer, but it does cite literature that appeared after Cutright wrote. Daniel Botkin (1995) used the expedition's natural history observations as a basis for his own comments on American environmental history. David Dalton's The Natural World of Lewis and Clark 2008 describes the natural environment they encountered and tells how it has changed since then. The bicentennial volume edited by Kris Fresonne and Mark Spence, Lewis and Clark: Legacies, Memories, and New Perspectives 2004 provides an historical perspective on the expedition, though none of the essays focus specifically on natural history. The National Geographic Society has published two books on the expedition, a very nice one by Snyder (1970) and a more spectacular one by Ambrose and Abell (1998). The history of the plants that Lewis and Clark collected is interesting but complex. Two collections of Lewis and Clark's plant specimens were lost to floods, but there are now 226 specimens in the Lewis and Clark Herbarium at the Academy of Natural Science in Philadelphia, and a good place to begin their study is the Herbarium of the Lewis and Clark Expedition (Moulton 1986–2001:XII). The list of species in Cutright's appendix (1969:399–423) is restricted to 178 plants previously unknown to science. After the expedition, Lewis arranged for Frederick Pursh (1774–1820) to describe their plant specimens (Jackson 1962:462–463, 485, Cutright 1969:359–356, Ewan and Ewan 2007:544). Pursh was employed by University of Pennsylvania Botany Professor Benjamin Smith Barton (1766–1815) to collect plants for an American flora that Barton never wrote (Ewan and Ewan 2007). According to Cutright on page 263, Pursh “described 124 plants collected by Lewis and Clark,” but on page 423 Cutright states that Pursh described 77 of the 178 new plants. Pursh (born Friedrich Traugott Pursch) was a capable German botanist who had come to America from England and returned to England to publish his Flora Americanae septentrionalis in 1814 (Ewan 1952, 1975a, 1979, Thomas 1997b, Ewan and Ewan 2007:501–520). To honor the explorers, Pursh named ragged robin Clarkia pulchella (collected on Clearwater River, Idaho 1 June 1806) and named bitterroot Lewisia reviviva (collected on Bitterroot River, Montana 1 July 1806). Pursh's Flora had only 24 species illustrated, 13 of which were from Lewis and Clark, including Clarkia (Fig. 6), but an illustration of Lewisia was not published until 1863 (Fig. 7). Pursh also named three new species after Lewis: wild flax (Linum lewisii), monkey flower (Mimulus lewisii), and syringe (Philadelphus lewisii). There are several books to help one sort through the botanical tangles. A good place to start is with Herbarium of the Lewis and Clark Expedition, volume 12 (1999) of The Journals of the Lewis & Clark Expedition (Moulton 1986–2001), which has an annotated list and photographs of 177 specimens. It also has a list of 176 species from Lewis' herbarium published by Pursh (1814) and photographs of Pursh's drawings of Lewis' plants, both published and unpublished. Johnsgaard's book commemorated the centennial of the expedition, as did three excellent books on the plants of the expedition that also appeared in 2003. Both Wayne Phillips' Plants of the Lewis and Clark Expedition and Scott Earle and James Reveal's Lewis and Clark's Green World are well illustrated with color photographs. Susan H. Mungar's Common to This Country: Botanical Discoveries of Lewis and Clark only discusses 25 species, but she does so in detail, and all are well illustrated in color by Charlotte S. Thomas. These books are indebted to Susan McKelvey's Botanical Exploration of the Trans-Mississippi West, 1790–1850 (1955:67–85), which still retains its usefulness. Two histories of botanical exploration discuss Lewis and Clark (McKelvey 1955:67–85, Coats 1969:293–295). Ragged robin Clarkia pulchella Pursh. Pursh 1814:I, plate 11, facing 261. Bitterroot Lewisia revivia Pursh. Pursh gave its specific name, because an apparently dead root was planted in Philadelphia and produced a live plant. (See Curtis' Botanical Magazine, series 3, volume 19, 1863.) Clark discovered the pronghorn on 6 September 1804, above the mouth of the Niobrara River, and on 14 September he killed a male near the mouth of the White River (now in South Dakota). He and Lewis later recorded numerous observations, as they frequently observed them on both sides of the Rocky Mountains (Burroughs 1961:140–146). Pronghorns were alternately shy and curious of humans. The explorers observed wolves run down one by taking turns in the chase until it tired. Pronghorns were most vulnerable when they attempted to swim across a river. Lewis and Clark sent skins and skeletons of a male and a female to Philadelphia, where George Ord (1781–1866) named and described it in 1815 and 1818. …discovered a Village of Small animals that burrow in the grown (those animals are called by the French, Petite Chien) Killed one and Caught one alive by putting a great quantity of Water in his hole. we attempted to dig to the beds of one of those animals, after diging 6 feet found by running a pole down that we were not half way to his Lodge, we found two frogs in the hole, and Killed a Dark rattle Snake near with a Ground rat (or prarie dog) in him, (those rats are numerous) the Village of those Covered about 4 acres of Ground on a gradual decent of a hill and Contains great numbers of holes on the top of which those little animals Set erect, making a Whistling noise and when alarmed Step into their hole. we por'd into one of the holes 5 barrels of Water without filling it. Those Animals are about the Size of a Small Squirel Shorter (or longer) and thicker; the head much resembling a Squirel in every respect, except the ears which is Shorter, his tail like a ground squirrel which they shake & whistle when alarm'd. the toe nails long, they have fine fur and the longer hairs is gray, it is Said that a kind of Lizard also a Snake reside with those animals (did not find this correct.) Lewis first saw the woodpecker later named for him on 20 July 1805 in Montana, and he described its appearance in detail on 27 May 1806 and observed it eating worms and a variety of insects (Burroughs 1961:239–241, Moulton 2003:319–320). The next day he also described in detail the bird later named Clark's Nutcracker and noted that it “feeds on the seed of pine and also on insects” (Burroughs 1961:251–252). On 6 June 1806 he also gave a detailed description of the Western Tanager, but did not observe what it ate (Burroughs 1961:256–257). Lewis later gave the remains of these three birds to Alexander Wilson to describe and illustrate (Fig. 9), and a grateful Wilson named two of them after Lewis and Clark (Mearns and Mearns 1992:143–146, 281–285). Afterwards, Wilson deposited them in Peale's Museum in Philadelphia (Cantwell 1961:141–142), where Lewis also deposited items he had collected (Sellers 1980:187–188). Both Lewis and Clark described the Sage Grouse in detail and saw it eat both grasshoppers and seeds (Burroughs 1961:213–215); Clark also drew it (reproduced in Thwaites 1904–1905, IV, facing 126, Cutright 1969:132). First illustration of Louisiana (= western) Tanager (Piranga ludoviciana [Wilson]), Clark's crow (= Nutcracker Nucifraga columbiana [Wilson]), and Lewis' Woodpecker (Melanerpes lewis [Wilson]). Wilson 1808–14: III, plate 20. Wilson's sketch for this plate was completed by his engraver, Alexander Lawson. Two of the fish they caught are illustrated in Lewis and Clark's journals. The sketch of the eulachon (Fig. 10) appears in both journals (Thwaites 1904–05, IV:Frontispiece), but since it is in Lewis' journal a day before it is in Clark's, it may be originally by Lewis. It shows the head pointing to the upper right corner of the page. Clark's illustration of the salmon trout (= steelhead trout Salmo gairdneri [Richardson]) is similar, but the head points to the top left corner of the page (reproduced in Thwaites 1904–1905, IV, facing 176, Andrist 1967:110). Their detailed accounts of these species includes descriptions, but otherwise concern Indian methods of catching them and their taste when cooked (Burroughs 1961:266–271, 263–264). Eulachon Thaleicthys pacificus (Richardson). Page from Lewis' journal for 24 February 1806. The same illustration from Clark's journal for 25 February 1806 is reproduced in Cutright 1969: following 240. Cutright's appendix on vertebrates (1969:424–447) is also limited to those previously unknown to science; it includes 17 mammals, 37 birds, 15 reptiles and amphibians, and 12 fish. Burroughs compiled Lewis and Clark's journal accounts on animals (Burroughs 1961); the lengths of these accounts are not in proportion to the number of new species discovered; there are 124 pages on mammals, 82 on birds, 9 on reptiles and amphibians, and 11 on fish. Jefferson rewarded the leaders of this successful expedition by making Lewis governor of Louisiana and Clark head of Indian affairs for Louisiana Territory in St. Louis. The consequence of their assuming these responsibilities was to delay publication of their journals; after Lewis' suicide Clark entrusted publication to a capable Philadelphia lawyer, Nicholas Biddle (Ambrose 1996:469–470, Jones 2004:185–200), who edited a two-volume abridgement of Lewis and Clark's journals (1814). Reuben Thwaites edited the first critical edition of the journals in 1904–1905, and Gary Moulton has edited a modern critical edition (1986–2001), including the Herbarium volume mentioned above. Jefferson also sponsored an expedition to explore the southern boundary of the Louisiana Purchase. In August or September 1805 he asked veteran government surveyor Thomas Freeman (d. 1821) to lead an expedition up the Red River (Flores 1984a:49, 2001:29–49, 2002, Stout 1999). In November Freeman went to Washington to discuss the expedition with Jefferson and to buy equipment. Then he went to Philadelphia to be tutored by the same scholars who had tutored Lewis in 1803, and to buy scientific equipment. Jefferson's letter of instructions for Freeman was similar to the one for Lewis (Flores 1984a:320–325). Jefferson then invited William Bartram to be the naturalist for this expedition. He declined because of his age, but on 6 February 1806 sent Jefferson a letter from Alexander Wilson volunteering for the position (Hunter 1983:249–251, Flores 1984a:57–58). However, Freeman had already chosen the naturalist in the first week of January 1806. Professor Barton had recommended to Freeman one of his medical students, Peter Custis (1781–1842), and both Custis and Freeman agreed (on Custis: Jackson 1981:228, 239, Flores 1997). Jefferson chose Captain Richard Sparks to lead the expedition's soldiers. In 1804 Jefferson had informed Spanish Boundary Commissioner, Caso Calvo, of the planned scientific expedition and had asked for a passport, which Calvo had granted. However, General James Wilkinson, a secret Spanish agent, advised the Spanish government in Mexico that the expedition would seek a route to Santa Fe and should be stopped, since Spain opposed Americans trading there (Flores 1984a:82–83). On 5 February 1806, U.S. Army Captain Edward D. Turner, with 150 soldiers, forced a Spanish garrison at Los Ades to withdraw to the Sabine River because Turner judged they were within Louisiana Territory (Flores 1984:86). The Red River Expedition left Fort Adams on the Mississippi on 19 April 06 and reached the Red River by 3 May, and Natchitoches on 19 May (Flores 1984a:101–103), where they learned that Spanish troops knew of their expedition and might stop them. Both Freeman and Custis kept daily journals. Custis also was given the responsibility of keeping daily meteorological records, and he was often pressed into surveying for a map (Flores 1984a:213). According to Freeman's estimate, considered accurate, they ascended the Red River for 615 miles, about half its length (map: Jackson 1981:232), before being confronted by a large Spanish army and forced to retreat downriver on 30 July. They were back in Natichitoches within a week (Flores 1984:206, 281). Custis seldom had as much time to observe and collect specimens as he wanted, but he did identify 22 mammals, 36 birds, 17 reptiles, fish, and amphibians, 4 insects, 58 trees, and 130 herbaceous plants (Flores 1984a:213). He discovered and named 22 species of plants and animals new to science, though he did not adequately publish his names and descriptions and received no recognition for them (Flores 1984b:41–42). His lists of plants observed on the expedition were annotated by C. V. Morton (1967), and Flores (1984a) incorporated Morton's information in his edition of Custis' journal. The extensive prairies which ar