86 EXPLANATIONS. 



found, animals mostly living far out at sea. To 

 put the case in its strongest form — foot-prints on 

 shores being the record of the birds of this era, 

 we are not to expect any trace of such birds as, 

 generally speaking, are not in the way of making 

 foot-prints on shores. I might go further than 

 this, and point out that certain natatorial genera 

 have feet not to be distinguished from those of 

 waders, so that certain of these foot-prints may be 

 those of natatorial species after all ; but I feel it 

 to be my best duty in the case, only to deny that 

 we are in circumstances to say that waders and 

 runners were the first created birds. Mr. Lyell, 

 who stands as high as this or any other writer on 

 geology, says, with regard to these very omithich- 

 nites, as they are called — " This sandstone is of 

 much higher antiquity than any formation in 

 which fossil bones or any other indications of 

 birds have been detected in Europe. Still we 

 have no ground for inferring from such facts, that 

 the feathered tribe made its first appearance in 

 the western hemisphere at this period. It is too 

 common a fallacy to fix the era of the first creation 

 of each tribe of plants or ajihnals, and even of 

 animated beings in general, at the -precise point 

 where our present retrospective Knowledge happens to 



