No. 433.] CERTAIN GROUPS OF BIRDS. 



37 



the names of Huxley, Dollo, Fiirbringer, Romanes, Seeley, 

 Woodward, and Zittel. Each and all of these writers have 

 taught that, by extremely slow and gradual development in 

 time, our existing birds were derived from ancestral reptilian 

 forms, and that the discovery of such a genus as Archaeopteryx 

 need create no surprise, for it represents just such a type as we 

 would look for far back in geologic time during the earlier 

 transitional stages in the evolution of the class Aves. 



The American Jurassic has also furnished fossil remains of 

 another land bird, but whether arboreal or not, as was the case 

 with A. UtJiographica, cannot be determined from the limited 

 material. It was a toothed bird of some considerable size, and 

 was described as Laopteryx priscus by Marsh, who obtained it 

 from the Jurassic of Wyoming. It is principally represented 

 by the posterior portion of a skull, and this, it is said, presents 

 a somewhat struthious character. The single tooth found 

 near this skull was more or less like the teeth possessed by 

 Ichthyornis. 



Beyond the fact, however, that Laopteryx probably belonged 

 to the same geological age as did Archaeopteryx, there is noth- 

 ing to indicate in the remains we have what manner of appear- 

 ing bird it was, much less as to whether it possessed a tail like 

 Archaeopteryx. It is provisionally placed here in the order 

 Saururae for convenience only. 



ORDER ORNITHUR/E. 



Fiirbringer employed the term Ornithurae to designate his 

 Subclass II of birds, created to contain all existing and extinct 

 species of this group of vertebrates not included in Subclass I, the 

 Saururae, which is represented alone by the fossil Archatopteryx 



