CYCADOFILICALES AND CYCADALES 299 



not a few examples of the existence of xylem of this type have 

 been described by Scott in the reproductive axes or cones. In 

 Fig. 212 is shown a transverse section of part of the peduncle of 

 the female cone of Stangeria paradoxa. Although the wood as a 

 whole is strongly centrifugal or peripheral in its development, a 



FIG. 212. Transverse section of one of the strands of the peduncle of the cone 

 in Stangeria paradoxa. 



small amount is formed over against the medullary region. This 

 condition is a persistence of the centripetal wood of the Paleozoic 

 Cycadofilicales, from which the Cycadales have in all probability 

 been derived. The anatomical principle here involved is one of 

 great importance and was first clearly emphasized by Scott. 

 Subsequent to his observations on the Cycadales, it has been 



