The structure & development of the mosses and ferns (Archegoniatae) . h less so in Tmesipteris. The leaves are smalland scale-like in Psilotum, larger and lanceolate in sporangia (or synangia) are bilocular in the latter, trilocularin Psilotum, and in both cases borne upon a small bilobedsporophyll. The development of the sporophyte has been carefullystudied by Solms-Laubach,^ who discovered that it multipliedrapidly by means of small gemmae (Fig. 251, k) produced ingreat numbers upon the subterranean shoots. These buds orbulblets are small oval bodies, but one cell in thicknes
The structure & development of the mosses and ferns (Archegoniatae) . h less so in Tmesipteris. The leaves are smalland scale-like in Psilotum, larger and lanceolate in sporangia (or synangia) are bilocular in the latter, trilocularin Psilotum, and in both cases borne upon a small bilobedsporophyll. The development of the sporophyte has been carefullystudied by Solms-Laubach,^ who discovered that it multipliedrapidly by means of small gemmae (Fig. 251, k) produced ingreat numbers upon the subterranean shoots. These buds orbulblets are small oval bodies, but one cell in thickness, andshowing usually a definite two-sided apical cell. Their cellsare filled with starch, and they sometimes remain a long time ^ Baker (2). - Bertrand (i, 2); Solms-Laubach (1); Bower (15). Solms-Laubach (i). XIV L 481 -dormant. These buds may produce others, but usually fromeach one is produced one, or sometimes more, elongated shoots,which develop into subterranean branches like those fromwhich the bud was originally produced. The young plant -sy--. Fig. 250.—Part of a vigorous plant of Psilotion triqiictrtiin (Sw.), about \. n, u, Subterraneanshoots ; a, a, the bases of aerial branches ; sy, synangia ; B, branch with two mature synangia,slightly enlarged ; C, a single opened synangium, showing the two lobes of the sporophyll belowit (after Bertrand). arising from the gemma is at first composed of uniformparenchyma, but in the later formed portions a simple vascularbundle is finally developed. No definite apical cell can bedetected in the earlier stages, but later each branch of therhizome shows a pyramidal initial cell, much like that in the 2 I 482 MOSSES AND FERNS CHAP. Ferns, but less regular in its divisions, and it is not possible totrace back all the tissues with certainty to this single branching is a true dichotomy, but is not brought aboutby the division of the original apical cell, but this becomesobliterated previous to the formation of t
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