PACHYPTEEIS. 



175 



specimens.' It is possible that Paohypteris {Bichopteris) Visianica 

 (Zigno) is specifically identical with P. lanceolata. An iateresting 

 ■example of Paohypteris has been described more recently by 

 Krasser from the Chalk of Lesiaa imder the name P. 



Text-fig. 27. 



This specimen ("Whitby Museum, No. 2376) represents an 

 imperfect pinna beariag thick pinnules, reaching a length of 

 1 cm,, in which the veias cannot be detected. 



Text-fig. 28. 



The original of "WiUiamson's drawing published by Saporta.' 

 As ia the Whitby specimen, the veias are not visible ; iu 

 this example several of the segments have a slightly lobed 

 margin, and bear a striking resemblance to those of Sdleropteris 

 JPomelii, Sap.* 



' Zigno (56), pis. xii. and xiii. 

 2 Krasser (95), p. 47, pi. ii. 

 5 Saporta (73), pi. xlv. fig. 3. 

 * Loc. cit. pi. xlyii. 



