. Elementary botany . Fig. 205. Rhizome of sensitive fern (Onoclea sensibilis). of cells. Two of the longer ones resemble the lips of some crea- ture, and since the sporangium opens between them they are sometimes termed the lip cells. These lip cells are connected with the upper end of the annulus on one side and with the upper end of the stalk on the other side by thin-walled cells, which may be termed connective cells, since they hold each lip cell to its part of the opening sporangium. The cells on the side of the sporangium are also thin-walled. If we now examine a sporangium from the bac
. Elementary botany . Fig. 205. Rhizome of sensitive fern (Onoclea sensibilis). of cells. Two of the longer ones resemble the lips of some crea- ture, and since the sporangium opens between them they are sometimes termed the lip cells. These lip cells are connected with the upper end of the annulus on one side and with the upper end of the stalk on the other side by thin-walled cells, which may be termed connective cells, since they hold each lip cell to its part of the opening sporangium. The cells on the side of the sporangium are also thin-walled. If we now examine a sporangium from the back, or dorsal Fig. 206. 1 to Under side of pinna of Aspidium edge as we say, it will appear as in the spinulosum showing fruit dots . r . - r TT (soil). left-hand figure. Here we can see how very prominent the annulus is. It projects beyond the surface of the other cells of the sporangium. The spores are contained inside this case.
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisher, booksubjectbotany
