128 



MEDULLOSEAB 



[OH. 



interpretation of the bract-like appendages is still an open question ; 

 they may have formed a cupular investment to seeds, but in the 

 Scotch species the general appearance rather suggests that they 

 may be microspore-bearing organs comparable with those of 

 Codonotheca^. There are no adequate grounds for supposing 

 Schiitzia to belong to the Coniferales, a view advanced by some 

 authors ; it is much more hkely to represent the fertile shoots 

 of a Pteridosperm. 



WHITTLESEYA. Newberry. 



The genus Whittleseya, referred by many authors to the 

 Ginkgoales, has no substantial claim to be regarded as alhed to 

 that group : its position is still uncertain, but the recent discovery 

 of fertile specimens suggests the probability of a relationship to 

 Potoniea and an identification of Whittleseya as another form of 

 microsporophyll of a Pteridosperm. 



Fig. 428. A, Cv Whittleseya elegans. A, single leaflet, from Pennsylvania. 

 (After Lesquereux; f nat. size.) C, diagrammatic sketch of 

 part of a leaflet showing the teeth, the striated texture of 

 the carbonised layer, and the vein-like markings on a lower 

 surface. (After Thomas; enlarged.) 

 B. Whittleseya brevifolia. (After White; the smaller figure f nat. 

 size.) 



The generic name was given by Newberry^ to some leaves, 

 or possibly leaflets, originally described by C. Whittlesey from 



1 See page 124. ^ Newberry (54). 



