THE GOLDEN-WINGED WOODPECKER. 
289 
consequently have the power of thrusting out their tongue td a much greater 
extent than others. Thus : 
In Picus varius, the tips of the horns of the hyoid bone reach only to the 
upper edge of the cerebellum, or the middle of the occipital region. 
In Picus pubescens, they do not proceed farther forward than opposite to 
the centre of the eye. 
In Picus principalis, they reach to a little before the anterior edge of the 
orbit, or the distance of 3 inch from the right nostril. 
In Picus pileatus, they extend to half-way between the anterior edge of 
the orbit and the nostril. 
Jl 
In Picus erythrocephalus, they reach to 3 twelfths of an inch from the base 
of the bill. 
In Picus tridactylus, they reach the base of the ridge of the upper 
mandible. 
In Picus auratus, they attain the base of the right nasal membrane. 
In Picus canadensis, they curve round the right orbit to opposite the 
middle of the eye beneath. 
Lastly, in Picus villosus, they receive the maximum of their development, 
and, as represented in the accompanying figures, curve round the right 
orbit, so as to reach the level of the posterior angle of the eye. Fig. 1 is a 
lateral view of the parts, showing the hyoid bones curving round the eye. 
Fig. 2 shows these bones as viewed from above. 
