466 



BBNNETTITAIiES 



[CH. 



the specimens consist of a central ovate body, approximately 

 3 cm. long, surrounded by several linear bracts (fig. 568, A). 

 The carbonised surface of the central region revealed on chemical 

 treatment a fairly regular pattern formed by the contiguous 

 polygonal ends of interseminal scales arranged round smaller 

 cylindrical micropylar tubes which project beyond the level of 

 the scales (fig. 568, B). This arrangement agrees closely with 

 that of the corresponding organs in Williamsonia and Cycadeoidea 



Fig. 568. Wielandiella 

 B, surface-view of 



Ua. A, conical receptacle with bracts, 

 and micropylar tubes. (After Nathorst; A, J nat. 



(c/. figs. 515, 564). In Wielandiella the micropylar tubes are of 

 uniform diameter and the cells of the epidermis have smooth 

 walls in contrast to the micropylar tubes of Williamsonia (fig. 563). 

 The strobilus in this state, before the scales and ovules have become 

 detached from the axis, may be described as a small Williamsonia, 

 but the habit of the stem is in itself a sufficient reason for the 

 use of a distinctive generic name^. 



A second species, Wielandiella punctata, described by Nathorst^ 

 from Scania is founded on pieces of forked stems associated with 

 fragments of a palisade-ring formed of contiguous segments 

 (microsporophylls) with microspores 58/jl in length. Fronds of 

 Anomozamites minor occur in the same beds. 



1 Nathorst retains the name Anomozamites minor for the leaves, restricting 

 Wielandiella to the plant as a whole including strobiii and stems which usually 

 occur in organic union [Nathorst (13)]. 



2 Nathorst (09) p. 25, PI. vn. figs. 14^22. 



