^"'ig'fe^^'] Shufeldt, Fossil Birds' Eggs. 8g 



Cormorants, Pheasants, and others, as may be seen by consulting 

 some of my former papers on the subject.* 



Nearly twenty years ago, Mr. Jno. Eyreman, of Easton, Penn- 

 sylvania, presented me with a collection of fossil bones of birds 

 and birds' eggs, which I subsequently described and presented to 

 the United States National Museum. f Among these specimens 

 I find three that are said to be fossil birds' eggs, and which, 

 apparently, from the records, were subsequent accessions. Mr. 

 Gilmore has very kindly loaned me all this material for a second 

 examination, though the eggs alone are of interest here. These 

 I have already passed upon, in part, in a list given on a former 

 page of this paper, and I need only add a few words in regard to 

 them in this place. One of these specimens, No. 6,496 of the 

 U.S. National Museum collection (fig. 12, Plate V.), is a very im- 

 portant one, as it not only presents about half of the- fossilized 

 internal matrix of a medium-sized egg (the divisional plane passing 

 roughly from apex to butt), but in addition it exhibits small areas 

 of egg-shell, adhering to the convex external surface of this matrix 

 in several places. What is even more interesting, it has, over- 

 lying these shell-areas in some places, remaining pieces of what 

 was originally a coating of pretty thick concretionary deposit. 

 This last was some ten or fifteen times thicker than the egg-shell 

 itself. I am of the opinion that a bird, and not a reptile, laid this 

 egg ; that originally it possessed an almost perfect ellipsoidal 

 form, and a true, thin shell. Its major and minor axes measured 

 about 50 X 38 millimeters respectively. 



As it is from the Oligocene of France, its history and fate may 

 have been practically similar to that of the fossil bird's egg found 

 in South Dakota by Mr. Gidley and described above. Its chief 

 importance lies in the fact that it presents both the shell of the 

 original egg — or, rather, its remains — and some of the overlying 

 fossilized calcareous deposits that encrusted the shell later on. 



In fig. 13 of the same plate is shown the remains of another 

 fossilized bird's egg from the same horizon in France (No. 6,497, 

 Coll. U.S. Nat. Mus.) Here we have an egg that was somewhat 

 smaller than the last ; and, while a very much larger part of the 

 shell has been preserved, no concretion or limy coating has formed 

 and fossilized upon it. This shell is sustained by the usual 

 internal, fossilized, coarse, pale grey matrix, upon which its much- 

 cracked-up pieces are closely adpressed. As this specimen has 

 been subjected to considerable pressure, and as less than half of 

 it was foimd, the exact form of the original egg cannot, with 



* Shufeldt, R. W., " Fossil Birds in the Marsh Collection of Yale 

 University," Trans. Com. Acad, of Arts and Sciences, vol. xix., pp. 54-60, 

 1915. There are those who are of the opinion that all birds of the Oligocene 

 must have been ratite forms. This is not true by any means, as anyone 

 may be satisfied through an examination of the work here cited. 



f Shufeldt, R. W., " Fossil Bones of Birds and Mammals from Grotto 

 Pietro Tampoin and Grive-St. Alban," Proc. Acad. Nat. Set. Phila., 1896, 

 pp. 507-516, plate xxiv., one figure in text. 



