THE YOUNG SPOROPHYTE 



59 



one, 1. e., the one turned toward the base of the root, the first leaf arises. It thus 

 appears that in these adventitious buds in Ophioglossum vulgatum there is much 

 the same arrangement of the first organs of the young bud that we have seen to be 

 the case in O. moluccanum, the leaf and the stem apex being virtually independent 

 organs. From Rostowzew's figures it is evident that the bundle from the first leaf 

 of the bud m 0. vulgatum is connected directly with the main root in very much 

 the same way as it is in the primary bud in 0. moluccanum; but apparently the first 

 : of the young bud is inserted higher up and does not connect directly with the 



root 



ip and does not connect directly 

 primary root; this point, however, needs further elucidation. Moreover, according 

 to his statements, there is a good deal of difference shown as to the time of the emer- 

 gence of the leaves and roots, three or four roots sometimes being well developed 

 before the first leaf expands. This reminds one of the behavior of the primary 

 sporophyte, where Bruchmann found that several roots were developed before the 

 first green leaf made its appearance. 



Fig. 40. — Vertical sections of a young sporophyte of Botrychium virginianum. The sections were cut at 

 right angles to the axis of the root. sA, sU'pular sheath of cotyledon; E, section of primary root, 

 which in this case was triarch, X20. 



THE YOUNG SPOROPHYTE OF BOTRYCHIUM. 



Jeffrey (Jeffrey 1) has described at some length the structure of the young 

 sporophyte of B. virginianum, and Bruchmann (Bruchmann 2) has studied the 

 earlier stages of the sporophyte in B. lunaria. The present account is based mainly 

 upon my own studies of 5. virginianum, made from material furnished me through 

 the kindness of Professor Jeffrey. Jeffrey found that from the beginning the con- 

 spicuous stele found in the axis of the young sporophyte was a hollow cylinder, 

 which he assumes to be a really cauline structure, and not made up of leaf traces. 

 The results of my own studies indicate that, as in the case of Ophioglossum, the 

 vascular system of the stem is made up exclusively of confluent leaf traces. 



Fig. 35, B, shows a longitudinal section of a young sporophyte in which the first 

 two leaves are evident and the continuation into these of the tissues of the vascular 

 bundle of the root is very clear. The large central pith continues up into the stem 

 apex, but the whole of the fibrovascular tissue is continued into the leaves, there 



