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FRAITHWATTE : THE STUDY OF MOSSES. 



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form a horizontal expansion without a stem or leaves, of which 

 the common Marchanfia is an example. 



The majority, however, constituting the Jungermanniacece, 

 have a branching stem and leaves, the latter l)eing often cut or 

 lobed, or having little pouches on the margin, and they are 

 usually arranged in two opposite rows, frequently with another 

 series of different form clasping the under-side of the stem. 



The capsule differs widely from that of mosses, bein 

 globose or ovalj without lid or peristome, and splitting into fou 

 valves, and the seta at base is fixed in an inflated cup or calyx ; 

 the spores also are accompanied with elaters, long thin hyaline 

 cells, on the interior of which run one to three spiral bands. 



The thallose section varies more in the fruit ; in Manhantia 

 the seta bears a radiate disc, on the under side of which are bi- 

 labiate perichostia, enclosing the sporogones, the male disc is 

 bluntly stellate, in the upper surface of which the antheridia are 

 immersed. Riccia and a few more have the reproductive organs 

 embedded in the substance of the frond. 



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We have been considering these plants as developed from 

 spores, but where no fruit is produced there are other modes of 

 propagation which ensure the continuance of die species; thus, 

 tubercles on the roots, gemnu^ on the stem or leaves, or even 

 a fallen leaf are all capable of producing protonema and new 

 plants. 



In collecting mosses we do not put them loose into the 

 vasculum, but wrap each specimen in paper, then, as soon as we 

 can, we prepare them for the herbarium by soaking in w^ater 

 until they are expanded, washing out dirt, and separating into 



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