BIRDS 



421 







m. 



f*"'-. 







^^^^-'^^^uijiiyijii^y^l^ 



Fig. 526.— The Central Fovea of the Swallow, Hirvsdo. 

 (Rochon-Duvigneaud). 



2A^'3?*ip-;ix?«v;vs^yji^^^Ss^gr&, 



..,.f:?;'^^*^•.'A's>l^i:;y*?^.'*^♦.^^^^* 





i^ «» *.* 



,t.v« »^,''''^f*^ 



,.1 **^* 



Fig. .527.— The Lateral Fovea op the Swallow, HiRvyoo. 

 (Rochon-Duvigneaud) . 



•-*^ 



YiQ, 528.— The Band-shaped Area of the Gannet, Sula 

 (Rochon-Duvigneaud). 



