MOSSES. 



[ -135 ] 



MOSSES. 



(BuxBAUMiA, fig. 97, p. 104) or at the tips 

 (fig. 484) into a membrane, or by a number 

 of cross-bars into an open trellis (fig. 488). 

 The rows of teeth are continuations of the 

 inner layers of tissue of the sporange (fig. 

 485), the outer wall of the sporange is, 

 as it were, continued by the operculum, 

 but ordinarily these do not separate directly 

 from each other when the lid falls ofi", since 

 one or several layers of elastic cells forming 

 a ring {a?inuhis, fig. 486) round the mouth, 

 split out from between the sporange and its 

 lid, and cause the latter to fall ofi". 



Allusion has been made to the sexual 

 import of the antherids and archegones, and 

 attention must be directed to the peculiar 

 phaenomena exhibited in the reproduction 

 of the Mosses. The embryo-cell of the 

 archegone appears to be fertilized by the 

 sphal filaments produced by the antherids ; 

 the result here is not the production of a 

 simple plant, but of a sporange or fruit 

 which produces a number of spores, each of 

 which may grow up into a new^ plant. 



Fig. 485. 



Fig. 485. Racomitrium fasciculare. Section of margin 

 of sporange, with a tooth of the peristome. Magn. 100 

 diams. 



Fig. 486. Bryum csespititium. Annuhis. Magn. 100 

 diams. 



Fig. 48". Orthotrichum diaphanum. Portion of double 

 peristome, the outer composed of teeth, the inner of 

 cilia. Magn. 50 diams. 



The Mosses exhibit a variety of forms of 

 vegetative multiplication. The lower part 

 of the stem often sends out horizontal 

 branches, which root and produce buds 



(fig. 489), from which arise new leafy stems, 

 and in this way patches of moss frequently 

 increase to a great size. They also produce 

 confervoid filaments, which exhibit tuberous 

 thickenings, a form of <7emm«(figs.492,493), 

 which may be detached from ea^h other like 

 bulbels, so as to propagate the plants with- 

 out any sexual reproductive organs. 



Gemmce or minute cellular tubercles, 

 capable of development into new plants, are 

 likewise met with, in other situations, as 

 in the axils of leaves, on the surface, the 

 margins (fig. 494), or at the tips (figs. 490, 

 491) of the leaves or the stems (fig.495); 

 these are formed of only a few cells at the 

 time when they fall off^, and illustrate well the 

 independence of the individual cells forming 



Fig. 488. 



Neckera antipyretica. 



Double peristome, the inner composed of teeth united 

 by cross bars, forming a trellis. 



Magnified 100 diameters. 



Fig. 489. 



Polytrichum undulatum. 



Creeping filaments with innovations. 



Magnified 5 diameters. 



the organs of these plants, where, under 

 peculiar circumstances, a single cell of the 

 tissue may be developed so as to lay the 

 foundation of a new plant. 



2 f2 



