104 



GEOLOGY. 



certainty, to the marsupial order. They appear to have been insectivo* 



rous. No certain evidences of placental mammals have been found. 



The insects. — The insects appear to have included members of 



Fig. 377. — The earliest known bird. Archceopteryx macrura. The long vertebrated 

 tail, the clawed digits of fore limbs, and the toothed jaws are ancestral features 

 to be specially noted. (H. v. Meyer.) 



nearly all the fossilizable groups that were not dependent on the angio- 

 spermous plants, directly or indirectly. As before, the neuropterous 

 and orthopterous orders predominated, the former represented by 

 well-formed dragon-flies, in addition to may-flies and termites; the 



