380 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1928 



a veritable cemetery of bird remains, mostly composed of the long 

 bones that are characteristic of fossil deposits. These thousands of 

 fragments were being steadily buried in the sands that blew in upon 

 them, so that the lagoon at Laysan may be a possible source of fossil 

 deposits for study in the remote future if then there still exist beings 

 interested or capable in such research. The situation on Laysan 

 suggests that similar conditions have operated on many oceanic 

 islands, and that there is opportunity for discovery of extinct forms 

 of life when these are found and properly exploited. Formation of 

 such large deposits seems to occur only under exceptional circum- 

 stances, it being more usual for scattered fragments to be preserved. 



The certain history of the class of birds as loiown in North Amer- 

 ica at the present time must be considered to begin with the Cre- 

 taceous period of geologic time. It is true that there is one species 

 called Laopteryx pt^hcus, described by Marsh from the Morrison 

 formation in southern Wyoming, that in late years, without par- 

 ticular reason, has been listed in the same family with Archaeop- 

 teiyx of the Old World. As there is, however, some doubt that 

 Laopteryx is actually avian, its systematic position must be con- 

 sidered vague until it has been more carefully studied. Another 

 fragment, described by Emmons in 1857 as Palaeonornis struthio- 

 risoides, from what are considered possibly Triassic beds in North 

 Carolina, is also so doubtfully avian as not to merit consideration 

 at this time. 



The first fragment of a fossil bird from this continent of which 

 we have record, a part of a tibia, was secured by S. W. Conrad in 

 the extensive marl beds near Arneytown, N. J. This was mentioned 

 in 1834 by Doctor Morton in his " Synopsis of the Organic Remains 

 of the Cretaceous in the United States," as a species of Scolopax, 

 but was not actually described until 1870 when Marsh bestowed upon 

 it the name Palaeotringa vetus. It is believed to be a primitive 

 member of the shore-bird group. 



The birds of greatest interest found in the Cretaceous period are 

 species known to have teeth, first described from specimens found 

 by Marsh, and parties working under his direction in the Niobrara 

 beds of western Kansas. Of prime importance among these are the 

 members of the family Hesperornithidae, in which there are at pres- 

 ent recognized five species. Several practically complete skeletons 

 have been discovered, so that in spite of their antiquity these fossil 

 forms are fairly well known (see pis. 3 and 4). The species of 

 Hesperomis were diving birds with greatly elongated bodies, strong 

 legs, paddle-like feet, and long necks, with the jaws set with sharply 

 pointed teeth placed in continuous grooves. The vertebrae were 

 saddle-shaped like those of modern birds. The lower jaw had teeth 

 set along the entire length, but in the upper jaw, teeth were placed 



