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stage of a fungus that draws its nourishment from the 

 living tissues of the leaves of violets. Of the fungi which 

 live upon decaying refuse matter, Ascobolus is one of the 

 more interesting among those selected for exhibition. In 

 this, the spores, or propagating cells, are borne in groups 

 of eight within transparent ellipsoidal sacs, and at maturity 

 these sacs, each enclosing eight spores, are ejected with 

 considerable force. Under the next microscope are shown 

 sections through the gills of a common mushroom, illustrat- 

 ing the manner in which its very minute and numerous 

 spores are borne. 



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. One of 

 these, a Frullania, has a part of each leaf peculiarly modi- 

 fied so as to form a reservoir for water. By aid of this 

 device, the frullanias and their allies are able to thrive in 

 drier situations than are in favor with most of the order to 

 which they belong. Preparations are exhibited showing 

 also the vegetative structure and methods of reproduction 

 of the true mosses. Especially interesting is the "peris- 

 tome" of one of the mosses, which is a fringe of peculiar 

 appendages surrounding the mouth of the little urn in 

 which the minute dust-like spores are borne. These ap- 

 pendages move about as a result of changing conditions of 

 moisture and these mechanical movements assist in scat- 

 tering the spores. A somewhat analogous device is found 

 in connection with the spores of the equisetums or horse- 

 tails, though the appendages in this case are attached to 

 the spores. Near the slide illustrating this feature of the 

 horse-tails is one showing the 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. Another preparation 

 shows the structure of the stem of the moonwort {Botry- 

 chium) as it appears in a cross section. Another illustrates 

 the structure of the wood of a young pine stem in cross 



