554 



THE AMERICAN NATURALIST 



[V..L. XL 



developed in the o;iills which are also strong of wing. Seeley says: 

 " Comparison shows that in so far as the i)ones are the same in the 

 bird and ornithosanr, the evidence of air cells entering them extends 

 to resemblance, if not coincidence in every detail. \o living gronp 

 of animals except birds ha^ ])neuinatic iiinb-l)one>, in relation to the 

 lungs; so that the identical structnrcs in the !> »nf- were due to the 



:01, p. 50). 



Brain. — In the avian brain the convergence' toward that of 

 the pterodactyl lies in the position of the o])tic lobes whic-li are lat- 

 erally displaced so that the cerebrum may extend between as well 

 as over them in order to abut against the cerebellum. There is 

 also a similarity in the development of the lateral lobes or flocculi 

 upon the sides of the hind brain. These features seem to be adap- 

 tations correlated with the development of flight. 



