172 SHUFELDT. 



EXPLANATION OF PLATE XVIII. 



Fig. 17. Head of Syrnium aluco ; right lateral view, with feathers removed 

 and showing ear-opening ; natural size. 



Fig. 18. Head of Syrnium aluco ; left lateral view, with feathers removed 

 and showing ear-opening ; natural size. 



Fig. 19. Skull of Syrnium aluco; basal aspect, with mandible attached; 

 natural size. 



Fig. 20. Skull of Syrnium aluco; superior aspect, with mandible attached ; 

 natural size. 



