30 MORPHOLOGY OF GYMNOSPERMS 



rangia once supposed to belong to the paleozoic Marattiaceae. This 

 throws suspicion on all sporangia of paleozoic "fronds." 



It is to be expected that among the Cycadofilicales there will be 

 found microsporangiate structures indistinguishable from the spo- 

 rangia of paleozoic ferns. This statement is emphasized by the fact 

 that even the stamens of the mesozoic Bennettitales bear synangia 

 closely resembling those of existing Marattiaceae. It would be useless 

 to consider here the numerous "fructifications," mostly those of 

 Pecopteris, which may or may not prove to be microsporangia; this 

 has been done recently by Scott (82). It is well to note, however, 

 that there is every gradation from naked branches bearing abundant 

 free sporangia (as Urnatopteris, whose sporangia have apical pores, 

 and which is strongly suspected of belonging to the Cycadofilicales), 

 to free and often solitary {Dactylotheca, also probably one of the Cyc- 

 adofilicales) sporangia on ordinary leaves, and finally to synangia of 

 various kinds (the radiate or Kaulfussia type prevailing). In Pecop- 

 teris Pluckenetii, whose seeds have been found. Grand 'Eury reports 

 (62) "stellate groups" of sporangia on the margins of pinnules, a 

 description applicable to the sori or incomplete synangia of marat- 

 tiaceous ferns. 



The danger of too hasty reference of sporangia to Cycadofilicales 

 is illustrated by Stauropteris Oldhamia, investigated by Scott (57). 

 Its very slender and numerous ultimate branchlets occurred " in dense 

 faggot-like groups," and bore terminal sporangia. The fact that the 

 ovules of Cycadofilicales are also often terminal on ultimate branch- 

 lets, and that some of the Cordaitales bear microsporangia in the 

 same way, made it tempting to infer that Stauropteris belonged to 

 the Cycadofilicales. Later, however, Scott (70) was fortunate 

 enough to secure preparations of the sporangia of Stauropteris con- 

 taining germinating spores, which showed distinctly their fernlike 

 character. The great interest of Stauropteris in connection with 

 Cycadofilicales, therefore, is to show that the terminal position of 

 sporangia on ultimate branchlets occurred among ferns. 



In any event, it is evident that the synangial microsporangia of 

 CycadofiHcales and the synangia of marattiaceous ferns were so much 

 alike as to imply common origin (74). 



