1887. | BOTANICAL GAZETTE. 290 
orders, all the larger genera, and the thallose, incubous and suecubous 
Jungermaniacee will be found represented. 
To procure specimens as free as possible (a by no means easy task) 
from other and misleading plants 
rom an examination of the set we are prepared to say that the 
specimens are admirable, and leave nothing to be desired. The labels 
are full and are accurately printed. We sincerely hope that the au hors 
will be liberally encouraged not only by the purchase of sets, but also by 
the contribution of material; and that the sets may soon begin to include 
the rarer species. Certainly, the enterprise is most commendable, and 
must prove of great benefit to all students of Hepaticze. 
Synopsis of the Flora of the Laramie Group. By Lester F Ward Sixth 
Annual Report of Director of the U. 8. Geological Survey, 1884-86. 
Washington, 1886; pp. 405-557, pl. 31-65. 
Perhaps no controversy over the stratigraphic position of any of the 
various members in the geologic series has been waged with greater 
persistency than has that over the position of the member now so well 
known as the Laramie Group. This group was first brought to light by 
the pioneer investigators of the geology of our western territories, and 
they, together with prominent paleontologists, from considerations of its 
animal remains, were led tu refer it to the cretaceous age. Others, 
equally eminent, basing their conclusions upon examinations of the plant 
as well as animal remains, argued for it a tertiary age So persistently 
have these two theories been attacked and defended that the subject has 
developed a copious literature of its own; and for the general student to 
attempt to read this and decide for himself is a nearly hopeless task. 
tertiary. : 
As itis now understood, this formation, which has a thickness of 
more than 4000 feet of strata, occupies a vast area, extending for hun- 
dreds of miles on either side of the Rocky mountains and from Mexico 
to far within the British possessions. This immense inland sea was 
first filled with brackish water, with at least one opening into the ocean ; 
but afterward, through the gradual cutting off of this avenue of inter- 
communication, it became nearly or quite fresh, The period of change 
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