432 G. E. Wieland — American Fossil Cycads. 



of cells (in the traDSverse longitudinal section only) with that 

 seen in a similar section of a nearly mature sporangium of 

 Angiopteris evecta given by Campbell in his "Mosses and 

 Ferns," fig. 143. The greatest difference would lie, of course, 

 in the absence of a rudimentary annulus, and the strong 

 development in the present forms of the outer prismatic layer 

 with the projection of its two valves beyond the sporangia to 

 meet lip-like on the line of dehiscence. It should be stated 

 that it would appear from the investigations of Bower (Studies 

 in the Morphology of Spore Producing Members) that the con- 

 dition figured by Campbell is not the usual one observed in 

 Angiopteris. If, however, it should approximate the condi- 

 tion seen in these fossil forms, we would then have indicated 

 in them imperfect septation of the loculi carried to a high 

 degree, an anomalous condition frequently noted in both Dance 

 and Marattia by Bower (loc. cit.). 



While, then, these cycad synangia may recall or suggest other 

 members of the living Marattiacese than Marattia, it is with 

 this genus that they may most closely be compared, agreeing 

 with it, as they do, in all essential structural details, as well as 

 in dehiscence, and doubtless also in development plurilocularly 

 from a single enclosed mass of sporogenous tissue. In fact 

 the parallel to Marattia is seen to be so close that had the 

 present structures been found isolated they might hitherto 

 have been referred directly to this genus, no pollen being pre- 

 served, unless indeed the remarkably strong and uniform pal- 

 isading of the outer layer, and its projection, as mentioned 

 above, beyond the sporangia into two lips meeting over the 

 sulcus between the two synangial halves, might have been con- 

 sidered characters of generic value. While it is quite possi- 

 ble that some little known Marattiacean forms may also show 

 a stronger development of the outer layer, it is not probable, the 

 heavy development seen in these cycads being apparently 

 secondary, and mainly due to the necessity for resistant strength 

 in the walls of the individual sporangia in their closely 

 appressed position before the inflorescence emerged fully from 

 the armor. 



Among extinct members of the Marrattiacese, Scolecopteris 

 vlegans Zenker of the Permian, long since so well and fully 

 described by Strasburger (Jenaische Zeitschrift, viii, 1874), is 

 likewise practically identical both in preservation and general 

 structure, including the bundles of the sporophyll. The main 

 distinction is, of course, in the lack of continuity in the outer 

 synangical wall, and the reduced number of the sporangia. 

 But as has been pointed out by Stur (Carbon Flora der Schatz- 

 larer Schichten) and later further emphasized by Bower (loc. 

 cit.), there is so much of transition in the amount of fusion 



