170 
scopes are shown sections of lichens, illustrating their mode of 
reproduction and the fact that a lichen consists essentially of two 
organisms, a fungus and an alga, intimately associated and con- 
stituting what for many purposes may be looked upon asa single 
organism. 
Then follow specimens of the liverworts or scale-mosses, plants 
in which the differentiation of the vegetative body into stem and 
leaves becomes first clearly evident. ne of these, a Frudlania, 
has a part of each leaf peculiarly modified so as to form a sac or 
reservoir for water. By aid of this device, the Frullanias and 
their ae are able to thrive in drier situations than are in favor 
with most of the order to which they belong. Preparations are 
pete Pome also the vegetative structure and met 
reproduction of the true mosses. Especially interesting is the 
“ peristome ” of one of the mosses, which is a fringe of seer 
about as a result of changing donditions of moisture and these 
mechanical movements assist in scattering the spores 
he app 
are attached to the spores. Following the slide illustrating this 
feature of Aguisetum is one anes the spores and spore-cases 
ejected, catapult-fashion. The remaining preparations show the 
structure of the leaf-stalk and root of common types of ferns. 
The aa aia exhibit is capa attracting much attention 
d with the ral additi and improvements of the future 
bids fair to re one of a most popular features of the 
Museum 
MarsHaLt A, Howe. 
