140 Seward and Gowan .— The Maidenhair 
against accepting all the fossil types of Heer and other authors. 
The species Ginkgo digitata , originally described by Brong- 
niart as a Fern 1 , is a common fossil in the Inferior Oolite beds 
of the Yorkshire coast, and one of the best examples of 
a Jurassic representative of the Maidenhair tree (Fig. 46, 
PL IX). The leaves of this species are in some forms practi¬ 
cally indistinguishable from those of Ginkgo biloba (Figs. 46 
and 54). Some of the smaller and more deeply lobed examples 
are usually referred to a distinct species, Ginkgo Hutto7ii 
(Sternb.), but these bear too near a likeness to some forms of 
the recent species (e. g. Figs. 63, 64, and 66 , PL X) to be 
specifically separated from the more typical examples of 
Ginkgo digitata (PL IX, Fig. 46). The fossil leaf shown in 
Fig. 69, Pl. X, from the Stonesfield slate, is probably not 
specifically distinct from the Ginkgo digitata (Brongn.), but it 
is of interest as affording evidence of the existence of the genus 
in the Stonesfield slate flora, from which it has not been pre¬ 
viously recorded. The Wealden leaves from North Germany, 
originally named by Dunker Cyclopteris digitata , Brongn. 2 , 
can hardly be distinguished from the Jurassic species. 
Among other species of Ginkgo and Baiera may be men¬ 
tioned Ginkgo Whitbiensis, Nath., Baiera gracilis, Bunb., B. 
Phillipsi , Nath., B. Lindleyana (Schimp.), all of which occur in 
British Oolite strata. From Northern latitudes Heer 3 has 
described numerous leaves which he refers to Ginkgo and 
Baiera ; from Siberia we have such species as Ginkgo pusilla , 
G. concinna (cf. Baiera gracilis), G. lepida (cf. Salisbnria nana, 
Daws. 4 , from Canada, B. Phillipsi , Nath., and Ginkgo sibirica, 
Heer), G. sibirica , G. digitata , Baiera longifolia, and B. 
pidchella. The specimens from Franz Josef Land described 
by Nathorst 5 and by Newton and Teall 6 as Ginkgo polaris 
1 Brongniart (’28), PI. LXI bis. 
2 Dunker (’46), Pis. I, V, and VI; and Schenk (71), PI. XXIV. 
3 Heer (’68-83), passim. 4 Dawson (’85 and ’93). 
5 Nathorst in Nansen (’97), Vol. ii, p. 486 . 
6 Newton and Teall (’97), PI. XXXVIII. [Since this was written, a fuller 
account of Ginkgo leaves from Franz Josef Land has been published by Nathorst 
in Part III of the Scientific Results of the Norwegian North Polar Expedition, 
1893 - 1896 , edited by Fridtjof Nansen.] 
