Development of the Vegetation of New York State 31 
ous foliage of maple and beech. No doubt they would seem 
weird, outlandish objects by contrast. So far as that goes, so 
do yucea trees of the dry plateaus of northern Mexico and so 
would many other arborescent forms of our present vegeta- 
tion, e. g., the giant cactus. 
The Age of Gymnosperms, Allies and Ancestral Forms 
of Pines, Etc. 
Imagine now the passing of, let us say, millions of years 
since the landmark which we selected in the Paleozoic era. 
Our second landmark or measure of the progress of plant life 
lies in the Jurassic period of the Mesozoic era. Even earlier 
in this era, the Triassic period, seed plants had displaced 
“spore plants ” (ferns and their allies) as the dominant veg- 
elation of the earth. Of the Triassic, Chamberlin and Sal- 
isbury’ Vol. III, page 38, say “ The Triassic was distinetly 
the age of gymnosperms the world over; the supremacy of 
the pteridophytes had ceased though ferns, true to their per- 
sistent nature, still held an important place. ” “The great 
lycopods were almost gone.” The Jurassic period is selected 
for our landmark rather than the Triassic because, not only 
did it show the same dominance of gymnosperms over pterid- 
ophytes thus marking a new era in plant life, but in this 
period there appeared forms of conifers of somewhat modern 
aspect being regarded as ancestral forms of our existing 
yews, cypresses, arbor vitas and pines. It was as Chamber- 
inn and Salisbury think ae ol. III, p. 94) the climax of the 
‘age of cycads” * * * ., “The ginkgos also played a 
somewhat important role.” There are a few scattered mod- 
ern remnants of the eyeads now living, one of which at least 
should be generally familar as the ‘‘ eyead palm.” So also 
is there a single living representative of the eroup of gym- 
nosperms known as ginkgos or G inkgoales, the beautiful Jap- 
anese maiden-hair tree. The species is a native of Japan, 
though widely cultivated. The conifer group of the gymno- 
sperms is as you well know, abundantly represented in the 
1 Chamberlin, T. C., and Salisbury, R. D. Geology. In three volumes. 
New York. Henry Holt & Company, 1906. 
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