292 L. F. Ward—Mesozoic Dicotyledons. 
Art. XXXITIL—On Mesozoic rit heady ; by Luster F. 
War : 
In the following remarks on Mesozoic Dicotyledons, I 
confine the term Dicotyledons to that sub-class of the vege- 
table kingdom which is embraced under the term Angzosperms 
in most modern text-books of botany. This is the usage 
of most vegetable paleontologists' and the reasons for adopt- 
ing it have been frequently stated.” 
The Dicotyledons occupy somewhat the same position in the 
history and development of plants that the Mammalia occupy 
They include nearly all the deciduous forest trees, the shrubby 
undergrowth, the leafy herbage and the weeds of all temperate 
regions, 
But this has not always been the case. In fact the reign of 
the Dicotyledons, geologically considered, has been very brief. 
Although there is evidence that the earth has been covered 
Tecognized group of the Cretaceous—the Urgonian. Until 
an the Miocene was so r é that it was with the Tertiary 
puke than with the Gees that the psn dominant — 
vegetation of the globe was assumed to have origin 
otwithstanding this, some of the earliest, if aa the very 
earliest, discoveries of these forms were in cretaceous strata. 
th 
In the stone-quarries of the Harz mountains near Blanken- 
_ burg, were found, near the ee mang of the eighteenth one 
prints of large leaves which the workmen believed to be t 
of the grape vine, and which were mentioned by Seheuchzeh - 
Wal oe 
Briickmann, and Walch, but without = attempt at their 
scientific determination. 
A brief historical review of the discovery, identification wed a 
ta of 
elesbingeets of dicotyledonous species in Cretaceous stra 
urope and America, including the arctic regions, will show the 
Esa which this subject is assuming among paleontolo- — a 
gists. ee 
" Géppert, Geinitz, and one or two others conform to the Jussiw#an system. 
? See the American Naturalist, vol. xii (June, 1878), de: 359-378. 
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