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Sclecteb motcB from tbc IRotc^^Boofte of the 

 postal nDicro6copicaI Society. 



Xlbe 3f ructttlcatton of flosses. 



By Thomas S. Beardsmore. Plate XV. 



BY putting these slides into circulation, I think I am touching 

 a subject which has not been brought before our members 

 during the period of my own membership. These small 

 plants always had a great attraction for me, and I once gave con- 

 siderable time and attention to their study, but increasing business 

 engagements compelled its discontinuance. So that preparing 

 these slides has been a great pleasure to me, and I trust that their 

 examination may not be without interest to our members. 



The objects on slide i are all parts of the fructification of the 

 mosses belonging to the natural family Polytrichace^, and are 

 intended to serve as an illustration of the construction of the 

 sporophore generation when it arrives at maturity. 



The PolytrichacecB are an exceedingly interesting group. They 

 d^iffer much in size and habit, varying in the British species from 

 one to eighteen inches in height. The British section includes 

 eleven species, but over two hundred are known. The stem is 

 highly developed, and in contradistinction to most other of the 

 Musci, it is characterised by a sort of central woody axis. This 

 family is usually regarded, especially when considering the noble 

 tree-like habit of some exotic species, as standing at the head of 

 all mosses. By reference to PL XV., Figs, i, 2, 3, those who 

 have not as yet paid any attention to the subject may more easily 

 follow the notes. 



The fructification of the mosses is called a capsule, and is 

 composed of a spore case, which varies in size and shape accord- 

 ing to the species, but the one under consideration may be seen 

 to consist of a tubular extension of the stem, or seta, in the shape 

 of a bent cylinder. This cylinder terminates in an annular 

 swelling called the " annulus," and upon which fits a lid called 

 the " operculum," which is here sub-hemispherical at the base, 

 and continued into a long beak. This lid falls off when the 



