1868.] BRAITHWATTE— ORGANIZATION OF MOSSES. 467 



minute organs, but his views were long opposed, for Roth and 

 Meese asserted that when sown, they produced young plants, and 

 hence were gemmae or buds. 



Fig. 7. Areolation of 

 Bryum ceespiticium. 



Fig. 8. Areolation of 

 Hypnum rutabuluro. 



As in flowering plants, we find the sexual organs present three 

 modes of arrangement, and the species may be : — 



Synoicous — when male and female organs are combined. 

 Monoicous — when they are separate, but on the same plant. 

 Dioicous — when separate, and on different plants. 

 The male or barren flowers are either terminal or lateral, and 

 consist of an involucre of minute leaves termed the perigonium ; 



Fig. 9. Leaf of Fissidens taxifolius. 

 these perigonial leaves vary in number, and in form and texture 

 differ considerably from those of the stem, becoming gradually 

 thinner and more delicate toward the centre. Some mosses have 

 no perigone, but the male organs nestle in the axils of the stem 

 leaves ; in others the flower terminates the stem as a beautiful 

 disc or rosette, well seen in the coloured heads of Polytrichum ; 

 and again it may be gemmiform, or like a minute bud composed 

 of a few imbricated leaves, as in Hypnum. 



Enclosed by the perigone are the antheridia, organs analogous 

 to the stamens of flowering plants; these vary in number, are 



