256 MESOZOIC FLORAS OF UNITED STATES. 



Genus ZAIMITES Brongniart. 



Zamites AKCTicrs Goppert. 



PI. LXVIII, Fig. 1. 



1864. Zamites arcticus Gopp.: Jahresber. d. Scliles. Ges. f. Vaterl. Cult., 1863, p. 84 



(nomen) . 

 1866. Zamites arcticus Gopp. : Neues Jahrb. f. Min., etc., 1866, p. 134, pi. ii, figs. 9, 10. 

 1885. Zamites sp. Dn.: Trans. Ro.y. Soc. Canada, Sect. IV, Vol. Ill, p. 7, pi. i, fig. 4. 



One specimen, which appears to be identical with the widely dis- 

 tributed Zamites arcticus Gopp., of the Lower Cretaceous, was found 

 at locality No. 19. This is a fragment of the lower part of a leaf show- 

 ing several leaflets. Although the fragment is small, and only a single 

 specimen was found, there can be no doubt as to the character of the 

 plant, as this type of fossil has so strongly marked features. It is clearly 

 a Zamites, of the type of Z. arcticus. The only question is to which 

 of the several species of this type it belongs. Among the Geyser fossils 

 (see pp. 306-310) are a number of imprints of a Zamites of the arcticus 

 type, belonging apparently all to one species, which shows some varia- 

 bility, indicating that several forms hitherto described as different 

 species are really slightly different aspects of Z. arcticus Gopp. Dunker 

 has described from the north German Wealden formation" a Zamites 

 of this type, which he calls Pterophyllum LyeUianum. This seems to 

 be a large form of Zamites arcticus. Besides the forms that he recog- 

 nizes as Z. arcticus, Heer has described a small Zamites of this type as 

 Z. brevipennis.'' Sir William Dawson has given, from the Kootanie beds 

 of Canada/' two forms of the arcticus type. One of these he names 

 Z. montana, and the other, depicted in fig. 4, pi. i, he leaves undeter- 

 mined. Both of these plants, as weU as Heer's Z. brevipennis, are prob- 

 ably Z. arcticus. This is indicated by the varying forms found in the 

 Geyser beds, which yield speciniens that agree well with the typical 

 Z. arcticus and with Dawson's plants, as well as with Z. brevipennis. 



The specimen from Cahfornia, now being described, is exactly like 

 the plant left undescribed by Dawson, but delineated in fig. 4. The 



" Monogr. d. Norddeutsch. Wealdenbildung, p. 14, pi. vi, figs. 1, la, 2. 



b Flor. Foss. Arct., Vol. Ill, Pt. II, (Kreide-Flora der Arctischen Zone) p. 67, pi. xv, figs. S, 9, 10. 

 <■ On the Mesozoic Floras of the Rocky Mountain Region of Canada : Trans. Roy. Soc. Canada, Sect . r\', Vol. 

 Ill, p. 7, pi. i, figs. 6, 6a, and fig. 4. 



