Animals Before Man 



western Kansas, and belong to at least two dis- 

 tinct orders. One, Odontolcce^ contains large, 

 flightless diving birds, having teeth imj^lanted 

 in a groove. The other, Odontotormce^ com- 

 prises species having teeth in separate sock- 

 ets, and some of the vertebrae with cup-shaped 

 ends, as in fishes ; the birds of this order so 

 far found are about the size of a small gull 

 and were gifted with the power of flight. 



The largest of these birds was Hesperornis 

 regalis^ the royal Western bird, a species some- 

 what larger than the king penguin of the 

 southern seas, measuring about 4| feet from 

 tip of bill to end of tail. Hesperornis was 

 very differently built from any modern water- 

 bird, being more elongate and narrower back 

 of the hip-joints, and with a much longer and 

 stronger tail. This would indicate that the 

 tail served as a sort of horizontal rudder, after 

 the fashion of those used in one of the new 

 submarine boats, to direct the course up or 

 do\vn. Turning to the right or left would 

 be readily accomplished by a slight change 

 in the direction of the stroke of one of the 



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