Bulletin 25 78 



(mxp), it is fair to presume that those delicate structures were 

 not found to be present in the fossil remains of Hesperornis ; 

 but, as there is every reason to believe that the bird possessed 

 rhem in its skull, I have restored them according to what we 

 find, with respect to their morphological character, in the 

 skulls of the Pygopodes found in the existing avifauna of this 

 and other countries. They were most likely elongate, scroll-like 

 bones that were well separated in the median line of the cran- 

 ium. 



Turning to the vomerine ossification, Marsh tells us, on page 

 7 of the "Odontornithes," that "The vomers in Hesberornis 

 are separate, as in lizards and a few existing birds.' ■ They are 

 smaller than the palatines, and resemble the vome s of Rhea, 

 more than those of the other Ratitce. They are broadest at the base, 

 which is obliquely truncated, and they taper gradually to the 

 pointed extremity in front (Plate II, figure 8 ). The thick, post- 

 erior end may possibly have united with the pterygoid, as well 

 as with the palatine. Both vomers are preserved in the skull 

 figured on Plate I. but are displaced." It is true, to be sure. 

 that we find double and independant vomers commonly among 

 lizards ; but there are no existing birds with separate, twin vo- 

 mers. The late Prof. William Kitchen Parker believed that 

 they so existed in the skulls of the woodpeckers {Picidce) ; but 

 he was mistaken in regard to it, as both Garrod and I subse- 

 quently demonstrated. Professor Huxley entertained the same 

 opinion that Professor Parker did ; but, as the latter states, 

 he had very indifferent material to study for the determina- 

 tion of such a point.* 



Personally I do not believe the vomers were separate in 

 Hesperornis, but that they w r ere simply broken apart in the 

 specimens Marsh examined. As to their resembling the "vom- 

 ers of Rhea," I may say that this is by no means the case, • 

 and much less do they in any way whatever resemble the vom- 



*Huxley, Thomas H. : "On the Classification of Birds ; and on the 

 Taxonomic Value of the Modifications of Certain of the Cranial Bones 

 Observable in that Class." P. Z. S., /S6/, pp. 448-449, fig. 30. 

 Parker, W. K., ; "On the Picida:." Trans. Linn. Soc, /S75, Ser. 2.. 

 vol. 1, pis. 1-5 ; also article, "Birds", Encycl. Brit., gt/i ed.. vol. Hi. 

 P.. 7/6. 



