546 . STUDIES IN FOSSIL BOTANY 



really double at its origin, and the analogy with Gnet- 

 aceae appears to be of little value. A comparison with 

 the female fructification of Ginkgo has been suggested, 

 and on general grounds would seem justified, but 

 the homologies of the parts have not been clearly 

 determined. However this may be, it appears evident 

 that, in the case of the female flower, the indications 

 of affinity point towards Coniferae or Ginkgoaceae, rather 

 than towards Cycadaceae, to which, so far as the floral 

 morphology is concerned, the Cordaiteae seem to bear 

 little resemblance. We must, however, remember that 

 our living Cycads only represent one or two special 

 surviving groups of a Class once infinitely more extensive 

 and varied. The possibility of a comparison between 

 the floral structure of the Cordaiteae and that of certain 

 Mesozoic Cycadophyta (the Bennettiteae) has been 

 maintained by some botanists, but no longer appears 

 tenable (see Chap. XIII.). 



6. The Seeds. — In some cases seeds, in a more 

 or less ripe state, have been found attached to 

 the inflorescence, and in connection with the leafy 

 twigs of Cordaiteae. These seeds sometimes appear 

 to have been solitary, a single seed representing the 

 female catkin as found in the younger specimens of 

 such fructifications as Cordaianthus Williamsoni. This 

 may indicate a real morphological difference, like 

 that between Taxus or even Ginkgoaceae and the 

 Coniferae with true cones, but it may be equally well 

 explained if we suppose that only one ovule in each 

 catkin developed into a ripe seed. In some specimens, 

 as in Cordaianthus anomalus, Carruthers, each seed 



