PACHYPTERIS. 



173 



do not afford any evidence of the existence of a single midrib 

 in the pinnules, as figured by Brongniart. In all probability the 

 thick pinnules were traversed by several veins, as shown in 

 Zigno's figures of Italian specimens. Saporta considers Pachypteris 

 ovata of Brongniart identical with Neuropteris Icevigata of Phillips, 

 and changes the latter name to Scleropteris lavigata ; the figure 



FIG. 27. Pachypteris lanccolata, Brongn. From a specimen in 

 the Whitby Museum, No. 2376. (Nat. size.) 



given by Saporta of this form is from a drawing by "Williamson 

 which was sent by him to Brongniart ; it was evidently made 

 from the Scarborough specimen shown in Text-fig. 28. There 

 is a close agreement as regards the habit of the frond and the 

 form of the pinnae between a large specimen described by Saporta 



