The structure & development of the mosses and ferns (Archegoniatae) . Fig. 173.—A-D, Development of the antheridium of O. ciniiainoniea, in longitudinal section,X425 ; E, F, G, three surface views of a ripe antheridium of O. Claytoniana; E, from above,Ihe .others from the side ; o, opercular cell, X425. wall arises in the apical cell, as in the Polypodiaceae, and thecentral cell has much the same form (Fig. 173, A). This hasno chlorophyll, and as usual the large distinct nucleus isembedded in dense highly refractive cytoplasm. There arenext formed in the outer dome-shaped cell two or three wal
The structure & development of the mosses and ferns (Archegoniatae) . Fig. 173.—A-D, Development of the antheridium of O. ciniiainoniea, in longitudinal section,X425 ; E, F, G, three surface views of a ripe antheridium of O. Claytoniana; E, from above,Ihe .others from the side ; o, opercular cell, X425. wall arises in the apical cell, as in the Polypodiaceae, and thecentral cell has much the same form (Fig. 173, A). This hasno chlorophyll, and as usual the large distinct nucleus isembedded in dense highly refractive cytoplasm. There arenext formed in the outer dome-shaped cell two or three walls,running more or less obliquely over the apex ; either at the topor at one side the last-formed wall encloses a small cell, whichis thrown off when the antheridium opens (Fig. 173, 0). Thisopercular cell, both in form and position, recalls strongly thatfound in the Marattiaceae. The divisions in the central cell correspond closely to those XI THE HOMOSPOROUS 345 in Ofioclea, but the number of sperm cells is larger, beingusually lOO or more. T
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Keywords: ., bookcentury1800, bookdecade1890, bookidstructuredev, bookyear1895
