Locality
From Hollick (1930) (p. 48)
"Yukon River, north bank, about 17 miles below Nulato (original No. 33); collected by W. W. Atwood and H. M.Eakin in 1907 (lot 4639) (pl. 11, figs. 2, 3). Yukon River, north bank, about 12 miles below Melozi telegraph station (original No. 3AH11); collected by Arthur Hollick and Sidney Paige in 1903 (lot 3248) (pl. 11, figs. 4-6). Yukon River, north bank, at Fossil Bluff, about 6 miles above Nahochatilton (original No. 2AC238); collected by A. J. Collier and Sidney Paige in 1902 (lot 2962) (pl. 11, figs. 7a,8)."
Description
From Hollick (1930) (p. 48)
"Ginkgo digitata (Brongniart) Heer, Regel's Gartenflora, Jahrg. 23, p. 261, pl. 807, figs. 1-3, 1874." (Heer 1874)
"Cyclopteris digitata Brongniart, Histoire des vegetaux fossiles, vol. 1, p. 219, pl. 61 bis, figs. 2, 3, Paris, 1830." (Brongniart 1830)
"Ginkgo huttoni (Sternberg) Heer, Regel's Gartenflora, Jahrg. 23, p. 261, pl. 807, fig. 4, 1874." (Heer 1874)
"Cyclopteris huttoni Sternberg, Versuch einer geognostisch-botanischen Darstellung der Flora der Vorwelt, vol. 2, pts. 5, 6, p. 66, Prag, 1833." (Sternberg 1833)
"Ginkgo digitata huttoni (Sternberg) Seward, Catalogue of the Mesozoic plants in the department of geology, British Museum, The Jurassic flora, pt. 1, p. 259, pI. 9, fig. 2, London, 1900." (Seward 1900)
"Ginkgo huttoni magnifolia, Fontaine, in Ward, L. F., Status of the Mesozoic floras of the United States, second paper: U. S. Geol. Survey Mon. 48, p. 124, pl. 31, figs. 4-8 ; pl.
32, figs. 1, 2; p. 170, pl. 44, figs. 7, 8, 1905." (Fontaine 1905)
Remarks
From Hollick (1930) (p. 48)
"Under this specific name I have included a number of lobed-leaved Ginkgos that vary more or less in size and in the extent and character of their lobation. Some would probably be referred without question to G. digitata (Brongniart) Heer, as that species is generally recognized, and others to G. huttoni (Sternberg) Heer. Some authorities have maintained a specific distinction between the two species; others have regarded them as varieties or leaf forms of a single species; and under one or the other name the stratigraphic distribution has been made to include the entire time period from Upper Triassic to Lower Cretaceous, and the geographic distribution to include England, Scandinavia, Russia, Siberia. Japan, China, Afghanistan, Australia, Iceland, the northwestern United States, and Alaska.
The multiplicity of forms and varieties that have been described and figured under the two specific names may be regarded as excessive; but, on the other hand, to attempt to differentiate them any further only results in greater confusion. In his discussion of the specimens from the Jurassic of Oregon, Fontaine (1905) (pp. 120 - 121) remarks: "I am not sure that they are not all modifications of the rather polymorphous species Ginkgo digitata (Brong.) Heer; and Knowlton (1914) (p. 55) in discussing the same species, says:
This genus [Ginkgo] has been very much overburdened, for in dealing with such an abundance of specimens and multiplicity of forms one must needs make either many "species" to accommodate this diversity or only one or two, and in view of the known variation exhibited by the single living species, the latter plan seems preferable. As a consequence, all the Alaska [Cape Lisburne] specimens are here considered as referable to the extremely variable Ginkgo digitata.
Following the same course of reasoning I have, therefore, included the series of diverse digitate and subdigitate forms from the Yukon River localities under the one specific name which, however, is to be regarded merely as an arbitrary arrangement with no more taxonomic significance than would be expressed by a differentiation into two or more so-called species and varieties.
Comparison may also be made with Ginkgo multinervis Heer (1882) (p. 46, pl. 5, fig. 1d; pl. 8, figs. 2b, 3, 4; pl. 9, fig. 3b) from the Atane beds of Greenland, which is strikingly similar to certain of the leaf forms included under Ginkgo digitata and may belong to the same species. In this connection reference may also be pertinent to a specimen from the Jurassic of Cape Lisburne, Alaska, referred to Ginkgo multinervis by Lesquereux (1888 [1889]) (p. 31, pl. 16, fig. 6)."