440 'Journal of Comparative Neurology ajrd Psychology. 



highest importance for sense psychology, as may readily be shown 

 by a single example. 



That part of the brain which in man and other mammals is 

 undoubtedly concerned with the sense of smell exhibits a constant 

 arrangement and microscopic structure, not only in them but 

 in all vertebrates down to the cyclostomes. We are therefore 

 thoroughly justified in the conclusion that an animal which 

 possesses this part smells, even though from its behavior nothing 

 may safely be inferred. Indeed \\^ may judge of the importance 

 of the sense of smell to the animal according as this organ is large 

 or small in relation to the remainder of the brain. 



The olfactory lobes vary greatly amongst the mammals, and 

 the following example which I select from the lizards enables you 

 to see that here, too, very considerable differences in the sense of 

 smell occur in different species. In Chameleon, which obviously 

 seeks its prey by means of the eyes, the roof of the mid-brain, 

 where the optic nerves end, is very large while the olfactory lobes 

 are extremely small. The nearly related lizards have enormous 

 olfactory lobes. It has long been disputed that birds possess a 

 sense of smell. Anatomy however shows us that they possess 

 true, although small, olfactory lobes. This simply and satisfac- 

 torily settles the much discussed question, and in fact there are 

 today observations enough which make the presence of an olfactory 

 sense at least very probable. The vulture and the eagle are 

 attracted by concealed prey and ravens find dead animals in a 

 thicket, even when they are deeply buried or covered with snow. 

 RoTHE saw in Lithuania, at a temperature of 24°, that the sea- 

 eagle scented out a dead animal deeply covered with snow, 

 uncovered it, and devoured it. The woodcock finds worms which 

 are deeply buried. It inserts the beak only to withdraw it with 

 a worm. A blackbird pecks industriously at the ground and digs 

 out a grub which lay fully five centimeters below the surface. It 

 must be that our ducks smell under water, for they dive suddenly 

 down into the mud and come up with full bills. The refraction of 

 the water must prevent their seeing anything on the bottom. 



The degree of development of the various parts of the palaeen- 

 cephalon will always give us information as to the possible activi- 

 ties of the animal. 



If, however, anatomy solves one problem, it suggests, as the 

 following shows, new problems in sense psychology. Probably 



