periods include a constantly increasing number of the higher 
forms. Thus, for example, in the cases representing Paleozoic 
time the plants are all thallophytes or seaweeds, pteridophytes 
or ferns and their allies, cycado-filices or cycad-ferns, and a few 
conifers. In the first case representing Mesozic time, contain- 
ing the plants of the Triassic and Jurassic periods, the majority 
consists of gymnosperms, both cycads and conifers, while in the 
next succeeding Mesozoic cases, containing the Lower and Upper 
Cretaceous plants, nearly all are angiosperms, many of them 
included in genera now in existence. The cases representing 
Neozoic time contain a constantly increasing number of living 
genera of angiosperms, until finally, in the last case, may be seen 
the remains of Quaternary plants which are indentical, both gener- 
ically and specifically, with our living flora. 
Coincident with this general arrangement, which illustrates the 
evolution of the vegetable kingdom as a whole, each case con- 
tains some individual specimens, or groups of specimens, which 
illustrate certain features or indicate certain phases of the subject, 
which are of interest to students in special lines of investigation. 
For example, most of the problematic fossils, those which have 
been ¢lassed by some authorities as the remains of plants and by 
others as traces of animals or as inorganic markings, may be seen 
in floor and wall cases No. 1 ; namely, Plamulina, which is prob- 
ably a hydroid; Phytopsis, whieh may bea coral; Scolithus, al- 
most certainly cau by worm burrows ; D. s phycus, which 
ay represent current markings; Dictyolttes, whi 
likely due to sun cracks, T , and others under the genera 
Paleophycus, Fucoides, Arthophycus, Archaeophyton, etc., have all 
been and some still are subjects of controversy as to their origin 
or relationships. In floor case No. 2 and floor and wall cases 
No. 3, are most of the fern-like plants, all of which were formerly 
thought to be true ferns, but many of which are now known, 
from critical study of the remains, to belong to an extinct order, 
Cycadofilicales, which had the outward appearance of ferns with 
fructification similar to that of the cycads or sago palms. Repre- 
sentatives of the interesting “ Glossopteris flora” may be found 
in floor case No. 5, —a flora of uncertain botanical relationship 
