171 



From a study of these two species it is evident that the history 

 of the young sporophyte is veiy different from that of any 

 other Pteridophyte, and in both species the definitive sporo- 

 phyte always arises secondarily as a bud upon the root in 

 the same way that there are so commonly formed adventitious 

 buds upon the roots of the adult sporophyte. Bruchmann notes 

 in 0. vulgatum the very precocious development of the primary 

 root and the late appearance of the stem apex and first leaf; 

 but in this species the shoot apex seems to be derived directly 

 from the epibasal half of the embryo, as it is in most 

 Pteridophytes. 



The youngest embryo found by the writer in 0. moluccanuin 

 (Fig. 116) had two cells. In this the basal wall was nearly 

 transverse, as it usually is in the eusporangiate ferns. 



In 0. i^endulum where the development of the embryo seems 

 to offer no check to the further growth of the prothallium, 

 the position of the archegoninm is very various, and it is 

 impossible to see from the section what the position was in 

 the living state, as the branches of the ga.metophyte extend 

 in all directions and archegonia may be formed at any point 

 upon their surface. To judge from the youngest stages of the 

 embryo that were met with (Figs. 118, 119) the basal wall 

 in this species is not necessarily transverse to the axis of the 

 archegoninm. In both of these cases it was oblique, but more 

 nearly longitudinal than transverse. It is very likely, however, 

 that it may be horizontal, or approximately so. In the four- 

 celled embryo shown in Fig. 118, the quadrant walls were at 

 right angles to each other, and this was also the case in the 

 five-celled embryo shown in Fig. 119. 



Somewhat older embryos (Figs. 117, 120) show that there 

 is a pretty regular octant formation, and Bkuchmann states 

 that this is also the case in 0. vuh/atutn. Bruchmann and 

 Jeffrey found a similar state of things in Botrychium. 



While in all typical ferns and in Botrychium all of the 

 organs of the young plant can be traced to certain regions of 

 the young embryo, in 0. pendiduui only a single one of the 



