Birds of the Priuicz'al World. 



141 



ostriches and other birds that are not made 

 for flying, there was no keel on the breast- 

 bone. 



While our friend the Hespcrornis was div- 

 ing after his dinner like a dart and making 

 things lively among the smaller fishes, the 

 Icthyornis sailed overhead on tireless wing, 

 pouncing 

 down oc- 

 casionally 

 on any 

 little fish 

 that ven- 

 tured near the sur- 

 face. The Icthyor- 

 nis was compara- 

 tively a small bird. 

 Two species have 

 been discovered, 

 one about the size 

 of a plover, and the 

 other nearly the size 

 of an ibis or curlew. 

 These birds had 

 quite slender legs, 

 like most of the 

 shore birds and 

 waders nowadays, 

 and long powerful 

 wings, and of course 

 they had a keel on 

 the breastbone, as 

 that is necessary for 

 the powerful mus- ^.^^^s 

 cles which keep the ^- ^_^_ ^ 

 wings ni motion. ^^i0i^^^^m^0Sff 



They had sharp ^^^'^-^'^sfe^^^'" " 



teeth which curved 

 back a little toward 

 the throat, so that a fish had not much 

 chance of breaking loose after the jaws 

 once snapped on him, but although the 

 Icthyornis had the marks of humble origin 

 in its backbone, it had quite an aristocratic 

 set of teeth, for each tooth was firmly set 

 in its own socket. 



A still more remarkable fossil bird called 



SKELETON OF ICHTHYORNIS RESTORED 



the Archicoptcryx has been discovered in 

 Europe in a little earlier page of the earth's 

 history. First the impression of a feather 

 was found in the rock, recording as plainly 

 as possible that the bird was there when the 

 rock was soft mud. After a while a very 

 complete specimen was discovered, and 

 wonderful to tell, 

 it had a long tail 

 like a lizard, and 

 the feathers grow- 

 ing on either side 

 of it. T\\&Archcc- 

 opteryx was a land 

 bird and had feet 

 like a perching 

 bird, and the body 

 was covered with 

 true feathers, but 

 in other respects 

 it was more like a 

 izard with its 

 ong tail and 

 toothed jaws. 

 The wings were 

 not very long, 

 and it is possi- 

 ble that it could 

 not fly upward, 

 but only like the 

 flying squirrels on 

 a downward in- 

 cline, and as the 

 fingers of its 

 wings were free 

 from each other 

 and armed with 

 sharp claws, it 

 must have been 

 a good climber. And so we must admit 

 that whatever may be thought of Darwin's 

 theory of evolution, there is at any rate not 

 a great dividing line which separates the 

 reptiles from the birds, and that in this 

 case the missing links are really just what 

 Darwin foretold — creatures midway be- 

 tween the birds and reptiles. 





NATURAL SIZE 



