THE WING-FINGER OF PTERODACTYLS, WITH RES- 

 TORATION OF NYCTOSAURUS 



S. W. WILLISTON 



The University of Chicago 



The question whether the wing-finger of pterodactyls is the 

 fourth or the fifth has been disputed for the past eighty years, 

 though for the past forty years authors have been almost unani- 

 mously agreed that it is the fifth. The first writer of credibility 

 who expressed an opinion on the subject was Cuvier, who con- 

 sidered it the fourth. His reasons for so doing, as published in his 

 Ossemens Fossiles, are today, I believe, unanswerable, and to him 

 should be given the credit, and not to H. v. Meyer, for the correct 

 recognition of the finger. I quote his remarks in full: 



En fin il a ce doigt enormement prolonge en tige grele, qui caracterise 

 eminement notre animal. 



II a quatre articulations sans ongle. Le quatrieme doigt des lezards aurait 

 cinq articles et un ongle; mais, dans les crocodiles, il n'a que quatre articles, et 

 il est depourvu d'ongle comme ici; seulement il n'y eprouve pas ce prolonge- 

 ment extraordinaire. 



Le crocodile et les lezards ont en outre un cinquieme doigt qui dans les, 

 lezards a quatre articles, et dans le crocodile est reduit a trois sans ongle. 



II parait que dans l'animal fossile il ne reste qu'un vestige de cinquieme 

 doigt, mais assez obscur et sujet a, contestation. 



Le grand doigt est probablement le quatrieme, car c'est aussi le quatrieme 

 qui est le plus long dans les lezards. 



Les trois autres le precedaient dans l'ordre inverse du nombre de leurs 

 articles. 



The first author to adopt the other view, that the finger is in 

 reality the fifth, was Goldfuss, who, as Plieninger has shown in his 

 full and reliable review of the subject, thought he saw in the pteroid 

 bone a first finger, accidentally misplaced in his specimen, and 

 in which he thought he recognized an additional phalange even. 

 H. v. Meyer early adopted Goldfuss' view, as shown in the following 

 quotation: "Es zeichnen sich diese Thiere vor alien anderen 

 wirklich dadurch aus, dass der Finger sie zum Fliegen befahigte, 



