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spores and spore-cases of the common polypody. The spore- 
case here is provided with a sort of spring, by the action of 
which the spores are violently ejected, catapult-fashion. The 
remaining preparations show the structure of the leaf-stalk 
and root of common types of ferns. 
c. Local Flora. In this collection it is designed to illus- 
trate every plant-species growing naturally or without culti- 
vation within one hundred miles of New York City. For 
the most part specimens of the plants themselves are used, 
but in cases where the structure of the plants renders this 
method undesirable, or impossible, a photograph or a draw- 
ing is substituted for the plant-specimen. This collection 
is displayed in swinging frames which are placed so as to 
correspond in a general way to the sequence of the cases of 
the synoptic collection already described ; thus, the first stand 
is near the first museum case as one enters the west hall from 
the top of the staircase. All of the plant groups are here 
represented by those members that occur locally, and the 
characteristics of the several groups as mentioned under the 
Synoptic Collection also apply here. 
3. THE MUSEUM OF FOSSIL BOTANY 
This collection, installed in the basement, is designed to 
show the successive stages of evolution through which the 
ancestors of our living flora have passed since the time of the 
first appearance of plant life on the earth, as far as the 
remains of extinct plants have been preserved. The arrange- 
ment adopted is therefore based upon the sequence of the 
geological time divisions: Eozoic, Palaeozoic, Mesozoic and 
Neozoic, and their sub-divisions into periods; Laurentian, 
Cambrian, Lower Silurian, Upper Silurian, Devonian, Car- 
boniferous, Triassic, Jurassic, Cretaceous, Tertiary, Quater- 
nary and Recent or Modern. This arrangement is therefore 
geological, but incidentally it is also biological, and is based 
on the same system as that on which the synoptic collection 
of the museum of systematic botany is arranged, inasmuch 
