JURASSIC FLORA OF DOUGLAS COUNTY, OREG. 53 



an age different from that of the locahties from which larger collections 

 were made. 



In estimating the fitness of these collections to give an idea of the 

 flora of the time in which the slates were deposited, we must bear in mind 

 that we can not judge from the mere number of specimens. The later 

 collections, which are by far the largest, were made under Professor Ward's 

 supervision, and in part by himself. From this cause the collections con- 

 tain a much larger proportion of specimens showing different plants and 

 significant parts of plants than they would contain if made by one unac- 

 quainted with fossil botany. In the latter case a large percentage of the 

 specimens are duplicates that throw no additional light on the character 

 of the plant or else are very vague impressions that can not be determined.. 



DESCRIPTION'S OF THE SPECIES. 



Class HEPATIC^. 

 Order MARCHANTIALES. 



Family MARCHANTIACE^. 

 Genus MARCHANTITES Brongniart. 

 Marchantites erectus (Bean) Seward?* 

 PL VI, Figs. 1, 2. 



1864. Fucoides erectus Bean in Leckenby: Quar. Journ. Geol. Soc. London, Vol. 



XX, p. 81, pi. xi, figs. 3a, 3b (erroneously numbered 2a, 2b on the plate). 

 1869. Haliseris erectus (Bean) Schimp. : Pal. Veg., Vol. I, p. 185. 

 1898. Marchantites erectus (Bean) Sew.: Fossil Plants for Students of Botany and 



Geology, p. 233, fig. 49 on p. 233. 



"I shall follow, as nearly as practicable, in this paper the system of Adolph Engler, as contained in Die 

 natiirlichen Pflanzenfamilien of Engler and Prantl, continued by Engler since the death of Prantl, and 

 perfected in the latest edition of his Syllabus. The names of the several groups, however, mil not be in all 

 cases those of Engler, but will conform to the new Code of Botanical Nomenclature adopted by American 

 botanists and published in May, 1904. In my first paper the Bryophyta, Pteridophyta, and Spermatophyta 

 were called subkingdoms of the vegetable kingdom in general. The American code proposes the term ''phy- 

 lum" for these, conforming to zoological usage. — L. F. W. 



'' Mr. Seward, in his Jurassic Flora of the Yorkshire Coast, p. 49, includes in the synonymy of this species, 

 without questioning them, the Fucoides arcuatus of Lindley and Hutton, pubhshed in 1837, and the Sphxro- 

 cocdtes arcuatus, which was the name given to this form by Presl in 1838, and takes up for a specific name 

 the Fucoides erectus of Bean, figured by Leckenby in 1864. If the Fucoides arcuatus is the same as the 



