THE QUEST OF PHYLETIC LINES 103 



respectively by Selaginella Willdenovii and Lycopodium clavatum. 

 Thus the error in comparing these isolated types on the basis of 

 mere transverse sections is that common one of comparing distal 

 phyletic results, which have been achieved along parallel lines 

 of advance. The similarities were not original but adaptive. 

 The error is in fact essentially similar to that in the comparison 

 of the moss sporogonium with the Hymenophyllaceous sorus. It 

 is in both cases to be corrected by a broader comparison which 

 brings to light the probable phyletic lines and shows that the types 

 compared are distal, and result from adaption along parallel lines, 

 rather than indications of phyletic similarity. 



Allusion may here be made to another opinion widely held in 

 earlier decades, which had its relation to phyletic views, viz. 

 the reference of sporangia to various categories of vegetative or- 

 gans. Thus the sporangium of a Leptosporangiate Fern was held 

 to be a metamorphosed hair, because of its origin from a single 

 cell : Eusporangiate sporangia were regarded commonly as emer- 

 gences: some ovules were held to represent pinnae or leaves, or 

 even vegetative buds, while occasionally pollen sacs or ovules 

 were regarded as being of axial nature. Such reference of propa- 

 gative organs to categories of vegetative parts was a natural con- 

 sequence of the pursuance of Goethe's theory of metamorpho- 

 sis into its ultimate detail. So long as our study is one of mere 

 comparison of the objective facts, as exemplified in organisms 

 now living, and without any consideration of their origin by 

 descent, such views may serve. But plainly they are inconsist- 

 ent with current beliefs as to descent. Throughout the whole 

 history propagative organs must have taken their place in each 

 completed cycle of life. There is every reason to believe that 

 organs of vegetation will have been evolved pari passu with pro- 

 pagative organs, and there is no reason to think that the latter 

 have been in any sense phyletically the result of metamorphosis 

 of the former, though it is possible that the converse may have 

 actually occurred. The source of the whole difficulty presented 

 by the theory of Goethe, and its derivative sub-theories, lay in 

 this general fact: that they were pre-evolutionary, or frankly 

 non-evolutionary. Otherwise they could not have left out of 



