382 ANNUAL EEPOBT SMITHSONIAN INSTITUTION, 192 8 



the two that are best known, in body were about as large as a 

 domestic pigeon. The neck was long, and the head was large and 

 strong, with long jaws implanted with many small, sharply pointed, 

 recurved teeth set in sockets. The wings were large, long and strong, 

 the sternum heavily keeled, and the legs and feet comparatively 

 weak. The biconcave vertebrae, which have the form found in 

 fish and some amphibians, and are unlike those of any other bird, 

 were the most peculiar feature of the group. Ichthy&imis was en- 

 tirely different from Hesji&rornis in that it was preeminently de- 

 veloped for flying. That it flew by feathers, and not by means of 

 a skin membrane as do bats, is shown by tubercles for the attach- 

 ment of secondary feathers on the ulna, and the ankylosis of the 

 metacarpal elements into one bone to form a firm support for the 

 primaries, the long wing feathers on the outer part of the wing. As 

 a flying form it is apparently nearer the central stem from which 

 have come our modern birds than is Hesperornis. Ichthyornis^ 

 however, shows primitive tendencies in that it still carried the am- 

 phicoelous or biconcave type of vertebral articulation, so that it 

 combines the ancient with the new, as a grandmother may don the 

 dress of a modern maiden. Ichthyoi'tiis has been postulated as 

 ancestral to modern terns or skimmers, but here again I believe that 

 resemblance is merely convergent, due to the restriction placed by 

 method in flight on the evolution of bodily form in birds. It is my 

 belief that birds of the Cretaceous had as varied form as those of 

 modern times, and that there is no direct linear connection between 

 the few fossils of this time yet known and existing groups. 



Certain other Cretaceous fossils {Apatonils celer and Baptornis 

 advenus) from the Niobrara beds are placed among the toothed 

 birds. From the evidence of Hesperornis and Ichthyomis^ the only 

 forms in which the jaws have been found, it would appear that teeth 

 may be a character to be expected in all ornithic forms of the Creta- 

 ceous, and that we should not, therefore, put any Cretaceous bird in 

 a modern family unless its skeleton is completely known. 



There are described from New Jersey three species of a genus known 

 as Palu\eotringa that are currently located in the modern family 

 Scolopacidae which contains the snipes, and three more of the genus 

 Telmatornis that are allocated in the family Rallidae among the 

 rails. Another, Laornis edvardsmnus, is considered as an anserine 

 bird of the family Anatidae that contains the ducks, geese, and swans. 

 These were supposed for many years to be Cretaceous forms, but 

 recent studies indicate that the particular marl beds of New Jersey 

 from which they come are not Cretaceous, but are in reality Eocene, 

 so that the birds indicated must be transferred to the Tertiary. 



With the beginning of the Tertiary period there is a sudden change 

 in our known fossil avifauna. Toothed birds have disappeared and 



