606 STUDIES IN FOSSIL BOTANY 



A. Rhodeanum, differing from the Cordaitean wood in 

 the arrangement of the pits and some other trivial 

 characters. 



Unfortunately, our knowledge of the Walchia 

 fructifications does not go much beyond their external 

 features. On certain specimens, small scaly cones 

 are borne, some of which were probably male, while 

 others are known to have been female ; in Walchia 

 filiciformis, Zeiller * showed that each scale of the 

 female cone bore a single seed, an important Araucarian 

 character. In a specimen described by Renault, on 

 the other hand, the lateral twigs each terminate in a 

 bud-Hke body apparently containing a solitary seed 2 

 ( Walchia frondosa, Ren.). On the evidence available 

 there appears to be some ground for referring such 

 a species as W. filiciformis to the Araucarieae, the 

 essential character of which lies in their fructification, 

 and especially in the carpellary scales, each of which 

 in the recent members of the family bears one ovule 

 directly, without the intervention of a seminiferous 

 scale. In vegetative characters there is also consider- 

 able agreement, but it appears most probable that 

 under the name Walchia very distinct types have 

 been confounded. It has been maintained that 

 Araucarieae are the oldest tribe of Coniferae ; this 

 statement, in the first instance, no doubt depended 

 largely on confusion between Cordaiteae and Arau- 

 carieae ; the former group is now excluded from the 

 question, but there is some evidence, as we have seen, 



1 Bassin houiller et permien dc briseflore fossile, 1892, p. 99, Plate xv. 



" Renault, Flore fossile d'Autun et d'Epinac, Part ii. p. 357, Plate 

 lxxviii. See also Potonie, Lehrbuch der Pjlaii'^cnpalaoiitologie, 1899, p. 

 292, for a general account of Walchia. 



