CORDAITALES 



175 



described by Oliver (14), and probably represent a more primitive 

 condition of the ovule than that of the Lagenosioma type. As stated 

 under Cycadofilicales, both types probably occurred in both Cycado- 

 filicales and Cordaitales; but as yet only the Lagenostoma type is 

 known to belong to the former 

 group, and only the Stephano- 

 spermum type has been asso- 

 ciated with the latter group. 



In Cordaianihus Grand 

 'Euryi (fig. 209) the bractlets 

 borne by the short ovuliferous 

 shoot are much larger, and a 

 very prominent and resistant 

 nucellar beak projects into the 

 micropyle and forms a passage- 

 way to the large pollen chamber. 

 The cells of the lower part of 

 this beak are transversely 

 elongated, narrowing the 

 passageway. 



The ovulate strobilus evi- 

 dently differs from the stami- 

 nate in being compound; that 

 is, a branch arises from the 

 axis of the strobilus to bear 

 the ovule. This character is 

 distinct from any tendency 

 shown by the strobili of the 

 cycadophytes, and is evidently 

 one that is continued in 

 those groups of Coniferales 

 (especially Abietineae) in which the "ovuliferous scale" is believed 

 to represent a reduced axillary shoot. Renault suggests a more 

 distant resemblance to Taxus, in which genus, as well as in Torreya, 

 the terminal ovules are borne on short fohage-bearing shoots. In 

 this comparison, however, while the ovuliferous branches are evi- 

 dently similar, the compact strobilus of Cordaitales is lost in the 

 branching of Taxus and Torreya. 



Fig. 207. — Cordaianthus Williamsonii: 

 longitudinal section of strobilus, showing 

 numerous sterile bracts and two ovules; Xio. 

 — kiier Renault (3). 



