698 S. W. WILLISTON 



Two years later Plieninger 1 discussed the subject fully and well, 

 reaching no positive conclusion, though evidently favoring the 

 Goldfuss view that the finger is the fifth. He showed that Goldfuss, 

 and not Fraas, as I had thought, was the first author to suggest the 

 identification of the pteroid with the first finger, and corrected 

 Seeley's statement that Meyer had so recognized it. We have seen 

 from the quotation that Seeley was really not so far wrong after 

 all, since Meyer did at one time consider the "Flugfinger" as the 

 "Ohrfinger." Finally Abel 2 in a recent paper has restated the 

 problem, adopting the original Cuvierian view. 



As bearing upon this question we have been fortunate in recent 

 years in determining the intimate structure of the hands and feet 

 of several of the early reptiles, from which I may say with entire 

 assurance that, until the close of Carboniferous times, and prob- 

 ably till the close of Permian times, the phalangeal formula for 

 reptiles was the primitive one of 2, 3, 4, 5, 3 for the front feet; 

 2, 3, 4, 5, 4 for the hind. Plieninger has raised a question in the 

 cited paper whether the formula 2, 3, 4, 4, 3, as seen in the 

 crocodiles, was not really the primitive one for the hands instead 

 of 2, 3, 4, 5, 3, as found in the generality of modern lizards and in 

 Sphenodon. In the accompanying figures the front limbs of three 

 of these reptiles, from the so-called Permian of Texas and New 

 Mexico, are shown, made out with certainty in nearly every detail. 

 In Fig. 4 the distal three phalanges of the fourth finger have not yet 

 been positively fixed, but inasmuch as the fourth digit of the hind 

 foot of the skeleton to which the figured hand pertains has definitely 

 five phalanges, there can be no doubt of the number in the same digit 

 of the hand. In Figs. 2 and 4 the bones of the forearm and wrist are 

 shown in a horizontal plane without the foreshortening of the 

 oblique position that they really had in life, and which is shown in 

 Fig. 3. Fig. 2 is that of a cotylosaur, probably belonging in the 

 suborder Pareiasauria, while Figs. 3 and 4, Ophiacodon 3 and Vara- 



1 "Ueber die Hand der Pterosaurier, " .Centralbl. fiir Minerdlogie, Geol., etc., 1906, p 

 399; also Paleontographica, LIII (1907), 301. 



2 "Die Vorfahren der Vogel," Verhandl. der K.K. zoologisch-bot. Gesellsch., LXI 

 (1911), 163. 



3 The full description of this genus will appear shortly in a paper by Dr. Case and 

 the writer. 



