1889.] ANATOMY OF PICARIAN BIRDS. 589 
seen to be connected with the antepenultimate ring. Although the 
last tracheal rings are not fused, they are very closely applied together 
and no membranous interspaces are left. 
Syrinx of Buceros rhinoceros, Front view. 
Ceratogymna elata, which is, like the last, a comparatively small 
species, has a very similar syrinx; indeed I can find no differences 
sufficiently tangible to be described. 
