Fossil Birds in the Marsh Colleciion of Yale University 29 



Aletornis bellus Marsh. 

 {Plate VI, Fig. 46.) 



Marsh, Amer. Journ. Sci., ser. 3, IV, 1872, 258. 



Holotype. Cat. No. 60, Peabody Museum, Yale University. Grizzly Buttes, 

 Wyoming. Eocene (Bridger). O. C. Marsh, collector. 



This species is based upon the distal end of a left tarso-metatarsal, 

 with its inner trochlear process broken off and lost. Neither this 

 fact, nor whether it belonged to the right or the left pelvic limb, are 

 stated by Marsh, who says in his article that "The tarso-metatarsal 

 is similar in its essential features to the same bone in the Killdeer 

 Plover {ALgialitis vociferus, Cass.), and about the same size." This 

 bone belonged to a bird not nearly as large as a Killdeer Plover, but 

 to a form of about the size of the Purple Sandpiper (Arquatella m. 

 maritima), with which I have compared it. (No. 17687, Coll. U. S. 

 Nat. Mus. "Tringa maritima.") In fact, I believe it represents 

 some Sandpiper of about that bulk. There is not enough of the speci- 

 men, however, to make even an approximate guess as to what kind of a 

 small Hmicoline bird it may have belonged to in life. It is just as 

 likely to have been a small Plover, or a Snipe of a similar size, and so 

 on. There are not characters sufficient in this specimen to enable one 

 to judge as to what genus it may have belonged to among existing 

 birds, even if the corresponding part of the tarso-metatarsi of all the 

 small limicoline species were at hand for comparison. It may have 

 belonged to an extinct species, as Marsh claims; but there is absolutely 

 no evidence at hand to prove that such is the case, and far less evi- 

 dence that the genus Marsh created to contain it is likewise an utterly 

 extinct one. 



All that I can say about this imperfect fragment of the left tarso- 

 metatarsus of a bird is, that it apparently belonged to some small 

 limicoline species of about the proportions of a medium-sized Sand- 

 piper, or Plover, or Knot, or an extinct diminutive Woodcock, or Snipe, 

 and so on through the list. This is all that is necessary at present to 

 state in regard to it; all that it will teach without additional material, 

 and all, thus far, that palaeontological science desires to know or to 

 make record of ; it is a positive detriment to that science to lumber up 

 the list of the extinct birds described, and described with more or less 

 certainty, with the names of genera and species, which have been 

 based on altogether too Uttle material, and of which we have so little 

 knowledge. 



