THE SENSE OF SMELL IN BIRDS 629 
under each box so that no visual hints of the location of the meat was 
conveyed. The vultures were very hungry, yet they did not leave their 
perches and come to the ground, although they had watched their keeper 
intently. He now re-entered and threw down one or two small bits of 
meat. Within a second or two, almost as the meat left the hand of the 
keeper, every vulture swooped to the ground and was hissing and strug- 
gling for a portion of the food. Twice the black vultures walked close 
about the meat box without appearing to notice the odor which was 
clearly perceptible, even to persons outside of the cage. A turkey vul- 
ture walked to leeward, instantly turned and made his way to the box, 
which he examined on all sides. He was soon joined by two others of 
the same species, and all three took up their stations close to the source 
of the odor. Soon two black vultures came up, apparently impelled 
more by imitation than by actual discovery of the smell. All five birds 
remained fcr a long time grouped close to the box, going to it now and 
then, and examining it carefully. Thus even in the turkey vulture the 
sense of smell is certainly not highly developed, and compared with the 
sense of sight, is defective indeed. 
The experiments of Benham (’06), gave evidence that Apteryx 
has an acute sense of smell. 
A preliminary statement of conclusions which were made from 
the experimental work described in this paper was published by 
the writer (Strong ’08). 
3. METHODS AND MATERIAL 
A. Morphological 
The olfactory lobes and nerves and the nasal chambers were 
studied in dissections of the bird head. As the olfactory lobes 
and nerves are always more or less imbedded in bone or cartilage 
and there is often considerable tough connective tissue directly 
over the lobes, dissection is not easy. <A pair of small, pointed 
bone-forceps were found especially useful for the larger heads. 
For very small birds, a pair of scissors with curved points, dissect- 
ing needles, and a lens were employed. Measurements were 
made with the aid of a pair of dividers of the breadth of the 
cerebrum and of its length in the median line. The length of 
the olfactory nerve from the apex of the olfactory lobe to the 
nasal chamber and the diameter of the olfactory nerve were also 
determined. Of course all of these measurements were approx- 
