RESULTS OF PAM;ONTOLOGICAL RESEARCH 75 



The Calamites we no longer find in the following 

 formations, but throughout the whole Mesozoic forma- 

 tions we find true Equisetse (like the modern ones with 

 slender branched foliage), as also in the Permian, Red 

 Sandstone, Jura, etc., which alter but little. Among 

 these are large forms, of which we retain an example in 

 the present Equisetum giganteum, ten to thirty feet high. 



It is to be expected that from the outset retro- 

 gressive phenomena should play a considerable role 

 in the history of the plant world and largely contri- 

 bute to shape new forms, but it might be difficult 

 to produce the necessary fossil proofs. We deduce 

 this rather from the so-called ' rudimentary ' structures 

 of the present plants, particularly parasitic ones. 



Conclusions deduced from palaeolithic botany. 



If it be granted that the forms of growth of syste- 

 matically higher rank appeared chronologically subse- 

 quently to the lower, yet there is absolutely no indicative 

 proof in the case of any one group (family or class) 

 that they were developed from the lower forms. In 

 this botanists are entirely in agreement in so far that 

 no one speaks of an actual ' proof ' which can be pro- 

 duced in the shape of fossil evidence of transitionalforms. 1 



1 See, for instance, Zittel's great work, the fifth volume of which is 

 elaborated by two distinguished botanists, Schimper and Schenk. The 

 expressions used of ' possibility,' ' perhaps,' etc., evidently show that no 

 proof has been afforded. Furthermore, see Reinke, ISchwendener, Haber- 

 landt, Potonie, Gothan, Steinmann, Kothen, Deperet, Kerner v. Marilaun, 

 and Neumayr. Certainly in many works we must differentiate between 

 what the authors represent as actual results of investigation in their special 

 lines and what they add thereto regarding ' general problems.' 



