MARATTIACEAE 



507 



the long petiole bears five palmately disposed lobes, of broadly lanceolate 

 form, with a general similarity of outline to the leaf of the Horse Chestnut 

 (Fig. 278, D). The venation, which is simple in other genera, of the 

 Neuropterid, Pecopterid, or Taeniopterid types, is more complex in 

 Kaulfussia, approaching that of the JDfynana-type. 



The roots originate internally close beneath the growing point of the 

 stem (Fig. 279) : in simple cases there may be one root to each leaf, 



FIG. 275. 

 A small plant of Dan<ifu alata. xk. J^ = stipules. (AftL-r Campbell.) 



but in strong plants the roots are more numerous. They take a course 

 obliquely downwards through the tissue of the stock, finally issuing as 

 robust roots which branch monopodially. 



Among Palaeozoic fossils radially constructed stems of greater length, 

 but showing strong analogies with the stems of modern Marattiaceae, 

 have long been known under the name of Caulopteris, when the external 

 surface is seen in the form of impressions ; or of Psaronius when the 

 internal structure is preserved. Among other points of similarity which 

 they show, the roots may be found traversing the cortex of these stems 



