162 Field Columbian Museum — Geology, Vol. II. 



I do not criticise Professor Marsh for making the restoration as he 

 did; he was perhaps justified, though it might have been better had he 

 stated how much of the restoration was conjectural, and had also pub- 

 lished a figure of the specimen as it actually was. 



In his present paper Mr. Eaton says: "At the present time of writing 

 an incomplete Pterodactyl skull is being worked out at the Yale Museum, 

 which will, in all probability prove to be that of Nyctodactylus Marsh. 

 The crest, which is apparently entire, is of small size compared with that 

 of Pteranodon, the measurement from occipital condyle to tip of crest 

 being only 49 mm., while the length from occipital condyle to tip of 

 beak was approximately 45 cm. In general the skull compares favorably 

 with that shown in Williston's restoration of Nyctodactylus, given in the 

 American Journal of Anatomy, Vol. I, No. 3, May 26, 1902, where he 

 states that the outline is taken in part from a specimen of Pteranodon 

 Marsh, or Omithostoma Seeley, as the genus was then called. It is there- 

 fore fair to infer that the apparent similarity of the two genera led Wil- 

 liston to draw inadvertently upon the characters of Nyctodactylus in mak- 

 ing his restoration of Pteranodon." 



Had Mr. Eaton done me the honor to have read more attentively the 

 article which he quotes; or had he examined the extended article on the 

 skull of Nyctodactylus with plates, published in the Journal of Geology for 

 August, 1902; or even had he examined the figure of the skull in Zittel's 

 text-book of Paleontology, published last autumn, of all of which he 

 seems strangely ignorant, he would have learned that Nyctodactylus has 

 no crest whatever, not even a vestige of one! It is very evident, therefore, 

 that Mr. Eaton has made the very error which he so freely suggests I 

 have made, and that his specimen is in reality a Pteranodon/ I am 

 pleased to learn that its "apparently entire" "crest" compares favorably 

 with that which I have assigned to the same genus. 



Now, since his own observations show that Pteranodon may have a 

 short crest, very much as I have figured it, it will be of interest to learn 

 more fully his reasons for attaching the elongated crest he has to the skull 

 as shown in Mr. Lucas's figure. I furthermore note that Mr. Eaton con- 

 tinues, in his "restoration" of the skull of Pteranodon, the gravest of the 

 inaccuracies of the original figures, the absence of the supratemporal 

 fossa and arch. If he is correct in this, the original reference of the 

 genus to a distinct order of reptiles was justified. But we will await fur- 

 ther evidence before assuming that he is, and meanwhile, it will be unfor- 

 tunate if his restoration finds currency. 



Inasmuch as Mr. Eaton has so clearly shown his ignorance of recent 

 and very accessible literature on the subject, it is too much to expect that 

 he would have mentioned the fact that the pelvis of Pteranodon has been 



