434 G. R. Wieland — American Fossil Cycads. 



tions it must, until additional fortunate discoveries are made, 

 as they doubtless will be, remain difficult to judge from isolated 

 fruits of the Marattian type whether or not they belong to 

 plants that have acquired the seed-bearing habit. When, how- 

 ever, preservation is unusually good the microspores may show 

 either pollen or spore characters, as in the case respectively of 

 the present forms and Scolecopteris elegans. At all events, an 

 extraordinary interest will henceforth attach itself to fructifi- 

 cations of the Calymmatothecan, and Scolecopteran type, as 

 well as to the possibility of accompanying macrosporophylls. 



It is of importance to add that the presence, in these cycada- 

 ceous forms, of a central ovulate axis surrounded by an asteriate 

 series of staminate fronds with basally adnate petioles, sheds a 

 flood of clear light on the nature of Williamsonia, —a subject 

 which has vexed paleobotany for thirty years. The axes which 

 Williamson and Saporta have described as male (see William- 

 son, Trans. Lin. Soc, Yol. XXVI, Plate 52, and many figures 

 in Paleontologie Francaise, Plantes Jurassiques, par Marquis 

 de Saporta,) are doubtless mostly ovulate inflorescences around 

 the bases of which were inserted the peculiar disks they have 

 illustrated, which may be interpreted as staminate rather than 

 " carpellary." Though that the central axis could terminate in 

 an asteriate growth is not wholly impossible. Such growths could 

 also be ovuliferous if apical and central, and calyxate if basal, 

 there being here great possibility of variant structures. 



However, in the writer's opinion the most important possi- 

 bility suggested by the staminate fronds above described is as 

 to the character of fructification in the Cycadofilices. If we 

 are permitted to imagine, as we surely are, a plant vegetatively 

 like Lyginodendron, and either monoecious or dioecious, with 

 microsporophylls like those of the staminate fronds of Cycad- 

 eoidea, and macrosporophylls like those of Cycas, do we not 

 picture an ancestral form which almost beyond doubt existed 

 and may any day be found? The existence of cones in the 

 presence of both these simple types of micro- and macro- 

 sporophylls is from the preceding descriptions now manifestly 

 possible. In the presence of such facts it is yet more patent 

 that there are peculiar possibilities of structure of great interest 

 in the case of such fructifications as that of Cycadospadix 

 Milleryensis. (See Scott's Studies in Fossil Botany, p. 371.) 

 Likewise, Anomozamites minor Brogn, from the Rhat of 

 Scania, as restored by Nathorst, is seen to occupy a position 

 of unique importance. It certainly becomes more than ever 

 probable that the dimorphism of various paleozoic plants 

 usually referred to the ferns is intimately connected with 



