habits I found that they do not fly at night, nor swim nor rest upon the water, and 

 yet are dependent upon the ocean for their food and water. This distance was 

 covered in a little less than six days. 



For comparison's sake I give here a record of the homing pigeon Hobo on his 

 trip from Houston, Texas, to Milwaukee, a distance of one thousand miles. I am 

 indebted to Mr. A. E. Wiedering, sometime race secretary of the Milwaukee dis- 

 trict of National Federated Homing Pigeon Fanciers, for the record of this bird. 

 He was one of Mr. Wiedering's prize birds. 



Hobo was released at Houston on July 24th at noon, and reached Milwaukee 

 on August 3d at a quarter past eight in the morning, taking nine days, twenty 

 hours and fifteen minutes for the trip (very close to the world's record). The one 

 other bird released with Hobo which made good time was Little Hen. Her record 

 was fourteen days, one hour and nineteen minutes. These birds had been flying 

 for five years, in large part over the territory lying between Houston and Mil- 

 waukee. 



There can be no doubt that my birds were carried into a wholly unknown 

 territory, and since they returned, the question as to how they did it is the one 

 which it is hoped future experiment will answer. The generally accepted theory 

 up to the present time has been that the birds return by means of visual landmarks, 

 but here there are no familiar visual landmarks. It seems to me that the "visual 

 landmark" theory of distant orientation is forever exploded by these tests. What we 

 shall put in place of it is difficult to decide. Birds may have an extremely sensitive 

 temperature sense, or a very fine sense of touch, which may aid them in detecting 

 warm or cold, wet or dry, violent or gentle air currents, but such a supposition is 

 doubly precarious for the reason that we do not at present know anything about 

 the perfection of their sense of touch and of temperature ; and, secondly, granted 

 that they have such senses finely enough developed, are the air currents constant 

 enough and distinctive enough to afford a basis for getting back from any point 

 of the compass? 



Shall we, then, assume a special homing sense and forthwith call our problem 

 solved? This might satisfy the dilettant, but not the scientist. If the facts 

 demand it, he is willing to assume a special sense, but the moment the assumption 

 is made it becomes his duty to locate the sense organ responsible for it and to tell 

 how the organ works, and what its relation is to the other sense organs. That 

 such a special sense, if it exists, is intimately related to vision in some way is 

 shown by the fact that birds, as a rule, do not fly at night and that blind birds 

 cannot find the way home. This may be due to the fact that light is necessary for 

 any kind of general bodily activity. Blind birds or birds kept in a photographic 

 dark room are at first almost incapable of taking care of themselves. They 

 behave much like birds whose cerebral hemispheres (the two largest portions of 

 the brain) have been removed. The fact that birds are helpless in the dark is no 

 proof that there is no special homing sense. All that we can say at present is that 

 light would be as necessary for the operation of such a supposed sense as it is for 



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